hi PLLSS HELP solve x2 – 8x = 20 by completing the square. Which is the solution set of the equation? {–22, 14} {–14, 22} {–10,
1 answer:
Answer:
{ - 2, 10 }
Step-by-step explanation:
Given
x² - 8x = 20
To complete the square
add ( half the coefficient of the x- term )² to both sides
x² + 2(- 4)x + 16 = 20 + 16, that is
(x - 4)² = 36 ( take the square root of both sides )
x - 4 = ± = ± 6 ( add 4 to both sides )
x = 4 ± 6
Thus
x = 4 - 6 = - 2
x = 4 + 6 = 10
You might be interested in
Answer: They can order from 0 to 449 bars, but no more.
Step-by-step explanation:
Given: The school band is ordering health bars to sell for a fundraiser. The company that sells the bars charges $0.40 per bar plus $20.00 for shipping regardless of the size of the order. The band must spend less than $200.00 on bars for the fundraiser.
The inequality below relates x, the number of bars that could be ordered, with the shipping costs and their spending requirements.
To solve for x, subtract 20 on both sides, we get
Divide 0.40 on both sides, we get
......... → the number of bars that could be ordered, with the shipping costs and their spending requirements must less than 450.
Thus, they can order from 0 to 449 bars, but no more.
Answer:
x = -9/2
Step-by-step explanation:
1. Divide 9 by -1/3:
÷
=
·
= -27
2. Divide both sides by 2:
2(x - 9) = -27
(x - 9) =
3. Add 9 to both sides:
x =
(or 4.5 if you need it in decimal form)
hope this helps!