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 ±
X=price of one jumbo popcorn
y=price of one chocolate chip cookies
$5.00=$5.00(100 cts / $)=500 cts
$6.00=$6.00(100 cts / $)=600 cts
We suggest this system of equations:
x+2y=500
x+4y=600
we solve this system of equations by reduction method.
-(x+2y=500)
x+4y=600
----------------------
2y=100 ⇒ y=100/2=50
x+2y=500
x+2(50)=500
x+100=500
x=500-100
x=400
solution: one chocolate chip cookie cost 50 cts.
Answer:
70%of x = 63
70/100 × x = 63
x=63×100/70
x=90
Step-by-step explanation: