In one sentence, describe what the following article is about: If your area experiences a period of drought, water the soil lightly to help the tree survive. Add enough water to moisten the soil about 3in (7.6cm) deep. You can test the soil by pushing your finger into it. If you can't push down to the roots easily, the soil needs water. An irrigation system works well for greenhouse growing. Give the guanabana plenty of fertilizer every year to help it grow and produce fruit. You can add fertilizer a month after planting or around March. Apply a second dose in early September. You can use a balanced 10-10-10 fertilizer from your gardening center, which has equal parts phosphorus, nitrogen, and potassium. Apply 14lb (0.11kg) of fertilizer in the first year, 12lb (0.23kg) in the second year, and 112lb (0.68kg) every year after that. Check the mulch layer before you add new fertilizer. Add a new layer of an organic material, such as compost or pine bark, in early spring. Then, you can finish tending to the tree by putting the fertilizer on top of the mulch. Replace the mulch every year to block out weeds and keep the surrounding soil moist. Wait for the guanabana's trunk to become at least 12in (1.3cm) thick. Using pruning shears, cut the branches down until the tree is about 30in (76cm) tall. Then, wait for new shoots to grow. Regular pruning helps your tree grow evenly so more water and sunlight reach the roots. New shoots will grow on your tree. Select the tallest shoot to be the central leader, then select 3 or 4 shoots spaced around it to be main branches. Wear a thick pair of gardening gloves and safety goggles to protect your eyes. Trim the central leader to about of its original size. New shoots will begin forming around the cut. Choose the tallest shoot again, then pin the other shoots down so they are horizontal. You can pin down the secondary shoots with clothespins or twine. Also remove any diseased or decaying branches on your tree. Although guanabana trees do not attract a lot of pests, some bugs can be an issue. Mealybugs are common, along with lace-wing bugs, moths, and fruit flies. Look for holes in the leaves, bark, or fruit. Spray a pesticide directly onto the plant. Consider using natural methods of pest treatment, like insecticidal soap or horticultural oil. Wear a respirator and eye protection when spraying chemicals. Keep people and pets out of the area. Root rot is a disease some guanabanas experience. This is usually caused by too much water.
Summary: Water the tree when the soil dries during a drought. Fertilize the tree in spring and fall. Renew the layer of mulch every year. Prune the tree down in the first year. Reduce the tree's size in the second year to encourage growth. Use an insecticide to treat infestations.

In one sentence, describe what the following article is about: The formula is D=w2+l2{\displaystyle D={\sqrt {w^{2}+l^{2}}}}, where D{\displaystyle D} equals the length of the rectangle's diagonal, l{\displaystyle l} equals the length of the rectangle, and w{\displaystyle w} equals the width of the rectangle. This method will only work if you are given the length of the diagonal and the length of the side of the rectangle. You might also see the formula written as D=w2+h2{\displaystyle D={\sqrt {w^{2}+h^{2}}}}, where h{\displaystyle h} equals the height of the rectangle and is used instead of length. The variables l{\displaystyle l} and h{\displaystyle h} refer to the same measurement. Make sure you substitute for the correct variables. For example, if you are trying to find the width of a rectangle that has a diagonal length of 5 centimeters, and a side length of 4 centimeters, your formula will look like this: 5=w2+42{\displaystyle 5={\sqrt {w^{2}+4^{2}}}} You need to do this to get rid of the square root sign, which makes isolating the width variable easier. For example:5=w2+42{\displaystyle 5={\sqrt {w^{2}+4^{2}}}}52=w2+42{\displaystyle 5^{2}=w^{2}+4^{2}}25=w2+16{\displaystyle 25=w^{2}+16} To do this, you need to subtract the squared length from each side of the equation. For example, in the equation 25=16+w2{\displaystyle 25=16+w^{2}}, you would subtract 16 from each side.25=16+w2{\displaystyle 25=16+w^{2}}9=w2{\displaystyle 9=w^{2}} To do this, you need to find the square root of each side of the equation. For example:9=w2{\displaystyle {\sqrt {9}}={\sqrt {w^{2}}}}3=w{\displaystyle 3=w} Don't forget to include the unit of measurement. For example, for a rectangle with a diagonal length of 5cm{\displaystyle 5cm} and a side length of 4cm{\displaystyle 4cm}, the width would be 3cm{\displaystyle 3cm}.
Summary:
Set up the formula for the diagonal of a rectangle. Plug the values for the diagonal and side length into the formula. Square both sides of the formula. Isolate the w{\displaystyle w} variable. Solve for w{\displaystyle w}. Write your final answer.