He made his mistake in Step 2. Tom should have subtracted 4/8 instead of 1/8. The mistake is that he was not consistent when he multiplied Denominators (bottom number) must be the same when handling fractions so Tom must multiply both the numerator and denominator by the SAME number to balance it out. 1/2 x 4/4= 4/8. Subtract. 7/8 - 4/8= 3/8. Tom has 3/8 of a gallon of paint leftover.
Answer:
1. Not accounting for the difference in the base of the exponent when applying the quotient rule.
2. Not subtracting the exponents of the denominator from the exponent of the numerator when applying the quotient rule.
Answer:
BC
Parallel: Two sides or lines are parallel if they are lines that are always the same distance from each other and will never intersect or touch
3a + 6b = 45
2a - 2b = -12....multiply by 3
----------------
3a + 6b = 45
6a - 6b = - 36 ...(result of multiplying by 3)
---------------add
9a = 9
a = 1
3a + 6b = 45
3(1) + 6b = 45
3 + 6b = 45
6b = 45 - 3
6b = 42
b = 7
solution is : (1,7)