Answer:
x=-7
Step-by-step explanation:
7x2-x=7
7x2=14.
14-x=7
When you finished the last step, you will subtract 14 to both sides.
14-x=7
14-14-x=7-14
this will cancel out the 14 on the left.
And will leave you with:
-x=7-14
7-14 is -7.
and this will get you to
-x=-7
To finish this off, you have to turn the negative x/variable, into a positive x/variable.
So, you will divide both sides of the equation by the same term.
-x = -7
into

and it will be -7.
I hope this helps :)
Answer:
20
Step-by-step explanation:
The two given and marked angles add up to 90.
A = x
B = 3x + 10
A + B = 90 Substitute for A and B. A and B are just letters I gave things.
x + 3x + 10 = 90 Combine the left
4x + 10 = 90 Subtract 10 from both sides.
4x +10-10 = 90-10 Combine
4x = 80 Divide by 4
4x/4=80/4
x = 20
Answer:
this is correct beacuse of the four in the back of the number six
Step-by-step explanation: