Answer:
Part 1) ![y=45x+150](https://tex.z-dn.net/?f=y%3D45x%2B150)
Part 2) The total charge is ![\$1,175](https://tex.z-dn.net/?f=%5C%241%2C175)
Step-by-step explanation:
Part 1) Write an equation in slope-intercept form to represent the total cost, y, of a project that takes x hours
Let
x ----> the number of hours
y ----> the total cost
we know that
The equation of the in slope intercept form is
![y=mx+b](https://tex.z-dn.net/?f=y%3Dmx%2Bb)
where
m is the slope
b is the y-coordinate of the y-intercept
In this problem we have that the charge of $45 an hour for a coding projects is equal to the slope m of the linear equation
so
![m=45\frac{\$}{hour}](https://tex.z-dn.net/?f=m%3D45%5Cfrac%7B%5C%24%7D%7Bhour%7D)
The y-intercept is the value of y when the value of x is equal to zero
In this problem the y-intercept is the total cost when the number of hours is equal to zero (the y-intercept is the start-up fee of $150)
so
![b=\$150](https://tex.z-dn.net/?f=b%3D%5C%24150)
The linear equation is
![y=45x+150](https://tex.z-dn.net/?f=y%3D45x%2B150)
Part 2) How much does the programmer charge for a coding project that takes 25 hours?
For x=25 hours
substitute in the linear equation and solve for y
![y=45(25)+150](https://tex.z-dn.net/?f=y%3D45%2825%29%2B150)
![y=\$1,175](https://tex.z-dn.net/?f=y%3D%5C%241%2C175)