I don't know the first one, sorry. But I know the second one

you want to cancel out a variable, so you can either substitute: x=-2y+2, so substitute -2y+2 in x in the other equation: 4(-2y+2)+8y=8 and solve for y (which will allow you to solve for x quite easily by plugging that # in for y in one of the equations)

or you can cancel out one of the variables by multiplying (this is my favorite way). Say you want to cancel out the y's. you can multiply the second equation by -4, which will get you -4x - 8y=-8

and then subtract this from the previous equation:

4x + 8y =8

-4x - 8y= -8

_________

0x 0y = 0

therefore, 0=0. This means that x can be any value (infinite solutions) whenever both variables are zero and the answer is zero (8-8=0), then there are infinite results.

If however, the answer is like 0x+0y=4, there is NO SOLUTION, because 0 cannot equal 4.

Hope this helps. Sorry it's really long haha

Call the questions T and O:

[The number of one-step equations and two-step equations who have been eliminated today is equal to 1070]

T + O = 1070

[! If three times the number of one-step equations minus twice the number of two-step equations is equal to 110]

3O - 2T = 110

Use equation 1 to express T in terms of O by subtracting O from both sides:

T + O = 1070 becomes T = 1070 - O

Substitute 1070 - O for T:

3O - 2T = 110 becomes 3O - 2(1070 - O) = 110

Multiply out:

3O - 2140 + 2O = 110

Simplify:

5O - 2140 = 110

Add 2140 to both sides:

5O = 2250

Divide both sides by 5:

O = 2250 / 5 = 450

There were 450 one-step questions.

What is the value of the x variable in the solution to the following system of equations?

4x + 8y = 8

x + 2y = 2

Dividing through equation 1 by 2 gives you equation 2:

What is the value of the x variable in the solution to the following system of equations?

(4x + 8y = 8) / 4 ==> x + 2y = 2

Since the equations are the same, the lines overlap and there are an infinite number of solutions. (answer 4)