I need help/guidance on some math problems!?

Question

I don't want answers just tell me how to solve them.

A) What is the solution set of the following system of equations?
x+y=7
x-y= 3

B) What is the value of x in the equation?
4(2x+10=273(2x-5)


C) The sophomore class at South High School raised $800 from the sale of tickets to a dance. Tickets sold for $1.50 in advance and $2.00 at the door. If a total of 475 tickets were sold, what was the number of tickets sold at the door? (Use Let Statements)

D) Find the solution set for this systems of equations?

x+y=8
y=x-3

E) 3/4 x-6=3

F) 2X+3Y=17
3X-2Y=-0.5

Answer 1

A. adding 2x=10 x=5
sub y=3

B.removing the brackets
8x+40=546x-1365
538x=1405
x=1405/538

C.x+y=475
15x+20y=8000
=>3x+4y=1600
3x+3y=1425
subtracting y=175
substituting x=300
so 300 tkts sold in advance
and 175 sold at the door

D.x+y=8
y-x=-3
adding 2y=5 y=5/2
sub x=11/2

Answer 2

A) x=5, y=2

Answer 3

Not in order:

A) x = 5, y = 2 (add the equations together)

D) Again, add the equations together (line up your Xs and Ys on one side, numbers on the other), then solve and substitute

x + y = 8
x - y = 3
------------
2x = 11
x = 11/2
y = 5/2

C) Let x = Advance tix
Let y = Door tix

x + y = 475
1.5x + 2y = 800

multiply top equation by 2
2x + 2y = 950
1.5x + 2y = 800

subtract the bottom equation

.5x = 150
x = 300

so, if x + y = 475, 300 + y = 475, y = 175

B) assuming the original eq is:

4(2x+10) = 273(2x-5)
multiply it out
8x +40 = 546x - 1365
combine
538x = 1405
x = 1405/538

Answer 4

A) First you have to solve one oy the equations for the variable

So x + y = 7 and x = 3+y

Substitute x (which is 3+y) everywhere you see x in the other equation....so

3 + y + y = 7

Combine like terms

2y = 4

y = 2 Sub 2 back into one of the equations as y and then solve for x (5,2)

B)Distribute to cancel out parenthesis

8x + 40 = 546x - 1365