Let's solve for y.
4x+7y=28
Add -4x to both sides.
4x+7y+−4x=28+−4x
7y=−4x+28
Divide both sides by 7.
7y/7=−4x+28/7
y=−4/7x+4
X= -12.5 you add (4+3) then, you combine it with 18 to get 25, then you divide 25 by -2x
I would say it’s better to buy the 36 box pens. 24\4.32=5.6 on the other hand the box of 36 is 36/5.76=6.25
Speed = distance / time
30 = d / 2.5
30 * 2.5 = d
75 = d
40 = d / 1.875
40 * 1.875 = d
75 = d
50 = d / 1.5
50 * 1.5 = d
75 = d
60 = d / 1.25
60 * 1.25 = d
75 = d
24 = 75 / time
time = 75/24
time = 3.125 hours
