I know, but I really am stuck with math problems..please help?

Question

a.) One number is 3 less than another. If 7 times the smaller number minus 3 times the larger number is 7, find the two numbers.

b.) Complete the ordered pairs for the equation y = 5x + 5.
(?,0), (4/5,?), (0,?), (-4/5,?)

c.) Find the slope of the line passing through the points (–2, 7) and (8, –1).

d.) An employee who produces x units per hour earns an hourly wage of y = 0.75x + 9 (in dollars). Find the hourly wage for an employee who produces 14 units per hour.

Thanks evrybody who helps out!!

Answer 1

a) x and y are your two numbers:
x = y - 3
7x - 3y = 7
Solve the two equations

b) If you are given the x-coordinate, that's x in your equation. Just substitute it in and solve. If you're given y, substitute as y and solve.

c) Slope is the change in y divided by the change in x.
(-1 - 7)/(8 - -2)

d) Substitute 14 for x into your equation.

Answer 2

1) Call a and b are those numbers. a is bigger than b. We have two equations :
a = b + 3
7b - 3a = 7
Solve those two equations, you'll get the answer.

2) Just plug those unknown pairs into the equation, we will find the unknown number in the pair.
Ex : (?, 0). we plug that into the equation :
0 = 5x +5 ==> x = -1. Therefore, the pair should be (-1, 0)
(0,?), do similar steps :
y = 5.0 + 5 ==> y =5 : the pair : (0, 5)

3) Call the line you're looking for is y = ax + b
Plug those pairs into equation respectively. you'll get two equations :
7 = -2a + b
-1 = 8a + b
Solve those two equations then you get values for a and b.
Put those a and b into the first equation : y = ax + b, you got the answer.

4) Simply, replace x by 14 and solve the equation for y. That is the answer.

P.S : If you don't know how to solve 2 equations, just type in google, "system of linear equation". Then learn how to do that kinds of problem. It will be helpful for further problems you may do.

Hope this help !!

Answer 3

b) Plug the variable into the equation (in the right place x for x, y for y) and solve for the missing one

c) Use the slope formula found in your text book