Answer:
{-2,10}
Step-by-step explanation:
x^2 - 8x = 20
Take the coefficient of x
-8
Divide by 2
-8/2 =-4
Square it
(-4)^2 =16
Add this to each side
x^2 - 8x+16 = 20+16
x^2 - 8x+16 = 36
The left hand side becomes( x + (-8/2) )^2
(x - 4)^2 = 36
Take the square root of each side
sqrt((x - 4)^2) =±sqrt( 36)
x-4 = ±6
Add 4 to each side
x-4+4 = 4±6
x = 4±6
x = 4+6 x = 4-6
x = 10 x = -2
They are both simple exercises in addition.
The solutions are:
(-65) x (-2) = <em>130</em>
(5j) + (10j) =<em> 15j</em>
Answer:
(x + 2)^2 - 11.
Step-by-step explanation:
f(x) = x^2 + 4x - 7
Now x^2 + 4x = (x + 2)^2 - 4 so we have:
f(x) = (x + 2)^2 - 4 - 7
f(x) = (x + 2)^2 - 11.
Answer:
x=3
Step-by-step explanation: