Answer:
Step-by-step explanation:
when x = 7 and y = - 2
3x + 4y
= 3 * 7 + 4 * (-2)
= 21 - 8
= 13
Hope it helps :)
Answer:
x = 1
x = -9
Step-by-step explanation:
(2x2 + 16x) - 18 = 0
2x2 + 16x - 18 = 2 • (x2 + 8x - 9)
x2 + 8x - 9
-9 + 1 = -8
-3 + 3 = 0
-1 + 9 = 8
2 • (x + 9) • (x - 1) = 0
2 = 0
x+9 = 0
x = -9
x-1 = 0
x = 1
x2 + 8x - 9 = 0
x2+8x = 9
(x+4) • (x+4) =
(x+4)2
x2+8x+16 = 25 and
x2+8x+16 = (x+4)2
(x+4)2 = 25
x = -4 + √ 25
x2 + 8x - 9 = 0
has two solutions:
x = -4 + √ 25
or
x = -4 - √ 25
- B ± √ B2-4AC
x = ————————
2A
A = 1
B = 8
C = -9
B2 - 4AC =
64 - (-36) =
100
-8 ± √ 100
x = —————
2
x = ( -8 ± 10) / 2
x =(-8+√100)/2=-4+5= 1.000
or:
x =(-8-√100)/2=-4-5= -9.000
Answer: x = 1
x = -9
Answer:
The question is false
Step-by-step explanation:
The <em><u>correct answer</u></em> is:
$72.31 – $24.61 – $16.49; $31.21
Explanation:
We know we end the month with $72.31.
We made two deposits during the month and no other activity. This means if we take the amounts of the deposits away from the total at the end of the month, we can find how much we had at the beginning of the month:
72.31-24.61-16.49 = 31.21