Consider the example
(3x+5) - (x-10)
When we subtract off the (x-10), we are basically subtracting off x and also subtracting off -10. This is the same as adding on 10 because -(-10) = 10
So we would have these steps
(3x+5)-(x-10)
3x+5-x+10
2x+15
Often students forget to distribute the negative all the way through and would have 3x+5-x-10 as an incorrect step. You need to multiply that -1 through to each term, so that's why the distributive property is used.
Answer:
-5
Step-by-step explanation:
3/4 = 9/12
2/3 = 8/12
9/12 - 8/12 = 1/12
So Johnny ran for 1/12 of an hour longer than Angie.
Answer:
(a) -20 1/2
Step-by-step explanation:
The proportion can be solved using "cross multiply" as the first step. This eliminates the fractions and turns it into a linear equation.
2/7 = -5/(x +3) . . . . . given
2(x +3) = -35 . . . . . . multiply by 7(x +3)
2x = -41 . . . . . . . . . simplify, subtract 6
x = -20 1/2 . . . . . . divide by 2
