A. because is $6 for every month as said in 6x, then an additional 12 for signing up, making 6x + 12 and she wants it to be under $60 so you use the less than sign making 6x+12 <60
We can set up a system of equations to solve this.
120b + 90d = 270
60b + 110d = 265
To cancel out b, first make the b terms equal.
60b · 2 + 110d · 2 = 265 · 2
120b + 220d = 530
Now subtract the equations.
120b + 90d = 270
-120b + 220d = 530
---------------------------
-130d = -260
Solve for d.
-130d/-130 = -260/-130
d = 2
Now put the value of d in one of the equations.
60b + 110d = 265
60b + 110 · 2 = 265
60b + 220 = 265
60b + 220 - 220 = 265 - 220
60b = 45
60b/60 = 45/60
b = 0.75
Each candy bar sells for $0.75
Hope this helps! :)
OK, so for this equation, your goal is to get the d, and ONLY the d, on one side of the equation. So, to start out, you need to multiply the entire equation, meaning both sides, by 8 because we are trying to get rid of those pesky fractions.
8(1/8(3d-2)=1/4(d+5))
The equation then turns into this because the 8 and 4 cancelled out with the 8.
1(3d-2)=2(d+5)
Now, we need to distribute the left over numbers into the parenthesis.
3d-2=2d+10
And finally, we need to get the d's on one side, and the numbers on the other, so we subtract 2d from both sides and add the 2 to both sides. They then cancel out to make
d=12
Hope it helps! :)