Answer:
y = 64 / 7
Explanation:
We can use Similar Triangle Theorem to find y.
The ratio of the "long leg to hypotenuse" of the large triangle is equal to the ratio of the "long leg to hypotenuse" of the medium triangle.
Therefore,
⇒ 8 : y = 7 : 8
Writing as fractions:
⇒ 8 / y = 7 / 8
Cross multiply:
⇒ 8 × 8 = 7 × y
⇒ 64 = 7y
divide both sides by 7
⇒ y = 64 / 7