Company A: y = 50x + 15
Company B: y = 130x + 55
Set the equations equal to each other and solve for x (number of weeks).
50x + 15 = 130x + 55
Subtract 50x from both sides:
15 = 80x + 55
Subtract 55 from both sides:
-40 = 80x
Did you have a typo? The companies will never have the same cost because company B costs so much more and weeks cannot be negative.
5x+7y=25
5x-2y=-65
subtract both of the equations
5x-5x=0
7y--2y= 7y+2y=9y
25--65=25+65=90
0+9y=90
9y=90
divide both sides by 9 to get y by itself
9y/9=90/9
cross out 9 and 9 which becomes 1*1*y=y
90/9=10
y=10
find x by using the substitution method
5x+7y=25
5x+7(10)=25
5x+70=25
move +70 to the other side
sign changes from +70 to -70
5x+70-70=25-70
5x=-45
divide both sides by 5 to get x by itself
5x/5=-45/5
cross out 5 and 5 then becomes 1*1*x=x
-45/5=-9
x=-9
answer:
(-9,10)
19 yards divided by 2.5 minutes.
=19/2.5
= 7.6 yards/minute
