Use completing the square to solve for x in the equation (x minus 12) (x + 4) = 9. x = –1 or 15 x = 1 or 7 x = 4 plus-or-minus S
2 answers:
Answer:
x = 4 ±
Step-by-step explanation:
Given
(x - 12)(x + 4) = 9 ← expand the left side using FOIL
x² - 8x - 48 = 9 ( ad 48 to both sides )
x² - 8x = 57
To complete the square
add ( half the coefficient of the x- term )² to both sides
x² + 2(- 4)x + 16 = 57 + 16
(x - 4)² = 73 ( take the square root of both sides )
x - 4 = ± ( add 4 to both sides )
x = 4 ±
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Answer:
Solution given:
1:
-1/8=
2. -64/27
=
Express in rational number
1. (-3/2)=-3/2*2/2=-(3*2)*(2/2)=-6/4
2. (1/5)=1/5*5/5=<u>5/25</u>
and
(-4/3)³(2/5)-⁴ ÷ (7/4)
(-4³/3³)(2-⁴/5-⁴)÷7/4
(-64/27)(5⁴/2⁴)÷7/4
(-64/27)(625/16)÷7/4
(-64*625/(27*16))*4/7
-2500/27*4/7
-10000/169
(-100/13)²