Albert needs $133 to buy a new hard drive. He earns $4.75 for each car he washes. If he spends $19 in supplies, write and solve an equation to find the number of cars he needs to wash to reach his goal.

Albert needs 32 cars to wash to reach his goal.

Step-by-step explanation:

We know that the slope-intercept form of a linear function is

where m is the slope or rate of change and b is the y-intercept

It is stated that Albert needs $133 to buy a new hard drive.

As earns $4.75 for each car he washes. Thus, $4.75 the rate of change or slope will be.

As he spends $19 on supplies. Since it is an expense, so -19 is basically the y-intercept 'b'.

Let 'x' be the number of cars he needs to wash to reach his goal.

Thus, substituting the value m = 4.75, y = 133, and b=-19 in the slope-intercept form of a linear function

y = mx+b

133 = 4.75x - 19

133+19 = 4.75x

152 = 4.75x

x = 152 / 4.75

x = 32

Therefore, Albert needs 32 cars to wash to reach his goal.

hello from mrbilldoesmath!

answer:

25x^2 + 90x + 84

discussion:

mn(x) = m(n(x)) = m( 5x + 9) =

(5x + 9)^2 + 3 =>

25x^2 + 90x + 9^2 + 3 =

25x^2 + 90x + 84                 (as 9^2 = 9*9 = 81)

which is the second choice

regards,  

mrb

p.s.   i'll be on vacation from friday, dec 22 to jan 2, 2019. have a great new year!