Question

Three lines of crops in a garden form a triangular shape. Strawberries are planted in a 10 ft line and green beans are planted in an 18 ft line. If the third side, a line of pumpkins, makes an 68 degree angle with the strawberries, determine the length of the pumpkins.

Answer 1

Answer:

$p = 19.18$

Step-by-step explanation:

This question is illustrated using the attachment and will be solved using cosine formula

$a^2 = b^2 + c^2 - 2bcCosA$

Let the strawberry side be s, the Green beans be b and the pumpkins be p.

The cosine formula in this case is:

$g^2 = s^2 + p^2 - 2spCosG$

Where

$s = 10$

$g = 18$

The equation becomes

$18^2 = 10^2 + p^2 - 2 * 10 * p * Cos\ 68$

$324 = 100 + p^2 - 20 * p * 0.375$

$324 = 100 + p^2 - 7.5p$

Collect Like Terms

$p^2 - 7.5p + 100 - 324 = 0$

$p^2 - 7.5p - 224 = 0$

Using quadratic formula:

$p = \frac{-b\±\sqrt{b^2-4ac}}{2a}$

Where

$a = 1$

$b = -7.5$

$c = -224$

$p = \frac{-(-7.5)\±\sqrt{(-7.5)^2-4*1*-224}}{2*1}$

$p = \frac{7.5\±\sqrt{56.25+896}}{2}$

$p = \frac{7.5\±\sqrt{952.25}}{2}$

$p = \frac{7.5\± 30.86}{2}$

$p = \frac{7.5 + 30.86}{2}$ or $p = \frac{7.5 - 30.86}{2}$

$p = \frac{38.36}{2}$ or $p = \frac{-23.36}{2}$

$p = 19.18$ or $p = -11.68$

But length can not be negative.

So:

$p = 19.18$