Answer:
x² + 7x + 10 = 0
Subtract 10 from both sides
x² + 7x = -10
Use half the x coefficent (7/2) as the complete the square term
(x + 7/2)² = -10 + (7/2)²
note: the number added to "complete the square" is (7/2)² = 49/4
(x + 7/2)² = -10 + 49/4
(x + 7/2)² = 9/4
Take the square root of both sides
x + 7/2 = ±3/2
Subtract 7/2 from both sides
x = -7/2 ± 3/2
x = {-5, -2}
Answer:
15cd(1 + 2cd)
Step-by-step explanation:
greatest common factor is 15cd
Answer:
y = -1/5 x + 2
Step-by-step explanation:
y = 5x - 4
m = 5
Slope of perpendicular = -1/5
Equation of perpendicular:
y = mx + b
y = -1/5 x + b
Use point (15, -1) for x and y, and solve for b.
-1 = -1/5(15) + b
-1 = -3 + b
b = 2
Equation of perpendicular:
y = -1/5 x + 2
The best step to do next is to add 80 to both sides of equation:
5 ( x² + 8 x ) + 80 = 14 + 80
and since 80 = 5 · 16
5 ( x² + 8 x + 16 ) = 94 Answer : B )
After that we will continue like this:
5 ( x + 4 )² = 94
( x + 4 )² = 18.8 ... etc
