Answer:
A
Step-by-step explanation:
Given
(- 12x + 4) + 
(6x + 8) ← distribute parenthesis
= - 9x + 3 + 3x + 4 ← collect like terms
= - 6x + 7 → A
Answer:
20%
Explanation:
What we know:
- there are 25 cans in total
- 5 of them are root beer cans
Using this information, we can say that 5/25 cans are root beer cans. To find the percent, we change the fraction into a decimal and then multiply it by 100.
To change 5/25 into a decimal, we divide the numerator and denominator.
5/25=0.2
And we multiply the decimal by 100 to get the percent:
0.2*100=20
Therefore, 20% of Cam’s cans are root beer cans.
I hope this helps!
1 )
1st and 2nd equation (multiply 1st by -2 ):
-2x - 10 y + 8 z = 20
2 x - y + 5 z = -9
---------------------------
- 11 y + 13 z = 11 / * ( -20 )
1st and 3rd:
- 2 x - 10 y + 8 z = 20
2 x - 10 y - 5 z = 0
-----------------------------
- 20 x + 3 z = 20 / * 11
----------------------------------
220 y - 260 z = -220
- 220 y + 33 z = 220
------------------------------
z = 0, y = -1, x = - 5
2 )
2 x - y + 5 = -4
- 2 x + 3 y - 5 = - 10
Substitution: y = 2 x + 9
- 2 x + 3(2 x + 9 ) = -5
4 x = - 32, x = -8, y = -7, z = 5
3 )
x + y + z = 11
1.5 x+3 y +1.5 z = 21
x = 2 y
------------------------
3 y + z = 11 / * (-2)
6 y + 1.5 z = 21
------------------------
- 6 y - 2 z = -22
6 y + 1.5 z = 21
------------------------
-0.5 z = -1, z = 2, y = 3, z = 6
Answer: the store used 6 pounds of peanuts, 3 pounds of almonds and 2 pounds of raisins.
