Ruby's hours will represent x+6
Svetlana's hours will represent 4(x+6)
Issac will represent x.
The equation would read:
x+(x+6)+(4(x+6))=126
x+x+6+4x+24=126
6x+30=126
Subtract 30 from both sides.
6x=96
Divide 6 on both sides to get x by itself.
x=16
So:
Issac worked 16 hours
Ruby worked 22 hours
Svetlana worked 88 hours.
To check your answer, plug in the values:
16+22+88=126
126=126
Hope this helps.
X-intercepts are found by factoring. Use the quadratic formula on the first since it's in standard form and you find that your x values are in fact -3 and 7. For the second one, use the Zero Product Property that says that x - 3 = 0 or x + 7 = 0. Therefore, x = 3 and -7. Signs are wrong. So not the second one. As for the third one, if you factor out a 3, your polynomial is exactly the same as the first one which did give us the desired x values. So the third one checks out. If you FOIL out the first one and then apply the quadratic formula you do get x = 3 and -7. So the fourth one checks out too. For the last one, putting it into the quadratic formula gives you x values of 3 and -7, so no to that one. Summary: 1st, 3rd, 4th have zeros of -3 and 7; 2nd and 5th do not.
