In rectangle abcd, ac = -x + 21, bp = -9x + 19, and dp = -y + 5. find the value of y.

y=-5

Step-by-step explanation:

see the attached figure to better understand the problem

we know that

The diagonals of a rectangle are equal and bisect each other

so

step 1

Find the value of x

substitute the given values

solve for x

Multiply by 2 both sides

step 2

Find the value of y

we have

substitute

substitute the value of x

ad = ae + ed = y + 7

similar triangles therefor

ac/ab = ad/ae

6/4 = (y + 7) / y

cross multiply

6y = 4(y + 7)

6y = 4y + 28

2y = 28

y = 14

step-by-step explanation:

step-by-step explanation:

compare