The correct answer is B = -1
10(1 + 3B) = -20
10 + 30B = -20
-20 - 10 = -30
30B = -30
B = -1
Hope this helps :)
Answer:
y=x+1/2z+-1/2
Step-by-step explanation:
Let's solve for y.
2x−2y+z=1
Step 1: Add -2x to both sides.
2x−2y+z+−2x=1+−2x
−2y+z=−2x+1
Step 2: Add -z to both sides.
−2y+z+−z=−2x+1+−z
−2y=−2x−z+1
Step 3: Divide both sides by -2.
-2y/-2 = -2-z+1/-2
y=x +1/2z+-1/2
For this case, the first thing we must do is define variables:
x = number of quarters
y = number of dimes
We now write the system of equations:
x + y = 28
0.25x + 0.10y = 4.05
Solving the system of equations we have:
x = 8.33
y = 19.66
Rounding:
x = 8
y = 20
Answer:
the college student has:
8 quarters
20 dimes
