7x+5y=-24 (1)
4x+y=42 (2)
multiply equation (2) by 5 to get
20x+5y=210 (3)
then calculate (3)-(2) which gives you
13x=234 hence x=18
then substitute for x in either equation to get y=-30
"Parallel" means the same, which means the slope you find. The formula for slopes is y=mx+b, so we need to put this equation in the right order for that. ('m' is the slope.)
Add 4x to each side, and get -3y=16+4x. Rearrange it to get it in the right order (y=mx+b).
This is -3y=4x+16. So the number in front of 'x' is 'm', which is the slope. You never actually see 'm', it is represented by a number. So four is the slope.
180 + 30x = 60 + 50x
⇒ 20x = 120
⇒ x = 6 minutes
<span>it will take 6 minutes for Millie to catch up with Ben</span>
She arrived to school at 8:08