Answer:

Step-by-step explanation:

Answer:
d
Step-by-step explanation:
Given y is directly proportional to x² then the equation relating them is
y = kx² ← k is the constant of proportion
To find k use the condition y =
when x =
, then
= k(
)² =
k ( multiply both sides by 8 )
1 = 2k ( divide both sides by 2 )
k = 
y =
x² ← equation of proportion
When y =
, then
=
x² ( multiply both sides by 2 )
9 = x² ( take the square root of both sides )
x = ±
= ± 3
with positive value x = 3 → d
Answer: correct answer is B.(2x+3y)(4x^2-6xy+9y^2)
8x^3 + 27y^3
(2x)^3+(3y)^3
(2x+3y)(4x^2-6xy+9y^2) <----answer
Explanation:
To find x we need to find the unknown side that connects the two triangles using the Pythagorean theorem:
a² + b² = c² (c is always hypotenuse)
So:
a² + 6² = 9²
a² = 9² - 6²
a² = 81 - 36
a² = 45
a = sqrt45
Now we do the same thing for the other triangle:
x² + 5² = sqrt45²
x² + 25 = 45
x² = 20
x = 2√5 or 4.5...