Answer:
x = 2±sqrt(11)
Step-by-step explanation:
x^2 -4x - 7 =0
Add 7 to each side
x^2 -4x -7+7 =0+7
x^2 -4x =7
To complete the square take the coefficient of the x term and divide by 2 and then square it. Add it to both sides
-4 /2 = -2 then square
(-2)^2 = 4
Add 4 to both sides
x^2 -4x+4 =7+4
x^2 -4x+4 = 11
Factor the left side into (x-b/2)^2
(x-2)^2 =11
Take the square root of each side
sqrt((x-2)^2) =±sqrt(11)
x-2 = ±sqrt(11)
Add to to each side
x-2+2 = 2±sqrt(11)
x = 2±sqrt(11)
Answer:
Step-by-step explanation:
<u>Given equation:</u>
<u>q is independent variable, we need to solve it for s:</u>
- 6q = 3s - 9
- 3s = 6q + 9
- s = 2q + 3
<u>Correct choice is </u>
Answer:
a is greater than or equal to 140
Step-by-step explanation:
Multiply both sides by 7, which cancels out the 7 and turns 20 into 140
