Allura, this is the solution:
As you can see we have two right triangles in the figure:
Therefore,
Step 1: Let's calculate the hypotenuse of the left triangle, as follows:
c² = a² + b²
c² = 12² + 18²
c²= 144 + 324
c² = 468
c = 21.63
Step 2: Let's calculate the sides of the right triangle on the right, this way:
Leg 1 = 21.63
Leg 2 = x
Hypotenuse = 12 + y
Height of the right triangle = 18
In consequence, to find the value of the hypotenuse and y, we have:
c = 21.63²/√21.63² - 18²
c = 468/√468 - 324
c = 468/12
c = 39
Step 3: Now, we can solve for y, this way:
39 = 12 + y
y = 39 - 12
y = 27
The correct answer is D. 27