Question 58202
solve for x and y

x+y=4
y=2X+1

the first equation subtract x to isolate y
y=4-x
substitute this equation for y in the second equation

4-x=2x+1
add x to each side
4=3x+1
subtract 1 from each side
3=3x
divide by 3 to isolate x
x=1

now substitute 1 into the first equation to find y
1+y=4
subtract 1 to find y
y=3

so x is 1 and y is 3