Answer:
25
Step-by-step explanation:
Answer:
The answer is B
Step-by-step explanation:
So let's say
x=number of five dollare bills
y=number of 1 dolar bills
20 bills total
x+y=20
totla is 72 monies
72=5 times x+1 times y=5x+1y=5x+y
solve
x+y=20
5x+y=72
from here you could do 2 things: go to option 1 (longer) or option 2 (shorter)
1.
x+y=20
subtract x from both sides
y=20-x
5x+y=72
subtract 5x from boths ides
y=72-5x
subsitute
y=20-x=y=72-5x
20-x=72-5x
add 5x to both sides
20+4x=72
subtract 20 from both sides
4x=52
divide both sides by 4
x=13
subsitute
x+y=20
13+y=20
subtract 13
y=7
2.
another way is when you got 5x+y=72 and x+y=20
you negative the second equaiton and add to th efirst
I know it sounds like voodo at first but it works
-(x+y=20)=-x-y=-20
add
5x+y=72
<u>-x-y=-20 +</u>
4x+0y=52
4x=52
divide both sides by 4
x=13
subsitute
x+y=20
13+y=20
subtract 13
y=7
Answer:
x = -1
Step-by-step explanation:
1/3(6x-3)+2(x-1) = -7
Distribute
2x-1 +2x-2 = -7
Combine like terms
4x -3 = -7
Add 3 to each side
4x-3+3 = -7+3
4x = -4
Divide by 4
4x/4 = -4/4
x = -1
