Answer:
36
Step-by-step explanation:
when solving for two variables, we need to find one variable in terms of the other.
so, we can turn:
x - y = 5
into
x - y = 5
+ y + y
x = y + 5
Then, we can substitute "x" in the given equation with "y + 5"
x² - y² = 30
(y+5)² - y² = 30
(y + 5)(y + 5)
F: y² O: +5y I: +5y L: 25 {foil}
y² + 10y + 25 - y² = 30 {cancel y² - y²}
10y + 25 = 30
-25 -25
10y = 5
÷10 ÷10
y = 0.5
x = y + 5
x = 0.5 + 5
x = 5.5
check:
(5.5)² - (0.5)²
30.25 - 0.25 = 30
30 = 30
(TRUE)
now, we must find the value of:
(5.5 + 0.5)²
= (6)²
= 36
So, the value of (x + y)² is found to be 36
hope this helps!!
Answer:
(x + y)² = 36
Step-by-step explanation:
x² - y² ← is a difference of squares and factors as
(x - y)(x + y) , then
5(x + y) = x² - y² = 30 ( divide both sides by 5 )
(x + y) = 6 , then
(x + y)² = 6² = 36
