Let the 1st number be x; 2nd number be y; 3rd number be z.
x + y + z = 79
x = number we are looking for.
y = x * 5 ==> 5 times the first
z = x + 16 ==> 16 more than the first
Therefor,
x + (x * 5) + (x+16) = 79
1st step, multiply the 2nd number: x * 5 = 5x
x + 5x + x + 16 = 79
Add all like numbers:
7x + 16 = 79
To get x, transfer 16 to the other side and change its sign from positive to negative.
7x = 79 - 16
7x = 63
To get x, divide both sides by 7
7x/7 = 63/7
x = 9
To check. Substitute x by 9.
x + (x * 5) + (x+16) = 79
9 + (9 * 5) + (9 + 16) = 79
9 + 45 + 25 = 79
79 = 79 equal. value of x is correct.
Answer:
B and F
Step-by-step explanation:
Given
x² + 4x + 4 = 12 ( subtract 4 from both sides )
x² + 4x = 8
Using the method of completing the square to solve for x
add ( half the coefficient of the x- term )² to both sides
x² + 2(2)x + 4 = 8 + 4, that is
(x + 2)² = 12 ( take the square root of both sides )
x + 2 = ±
( subtract 2 from both sides )
x = ±
- 2
= ± 2
- 2
Hence
x = 2
- 2 → B
x = - 2
- 2 → F
.0000000083
( eight zeros.)
Answer:
$1030
Step-by-step explanation:
Last winter:
Total expense = 370 * 2.56 = $947.2
Next year,
price increases 9% per gallon
which means, per gallon cost is $2.7904
Approx. expense = 370 * 2.7904 = $1032.448 which is round down to $1030