How can you solve y-x=28 and y+x=156 using elimination?

Astore sells two types of radios. one type sells $87 and the other for $119. if 25 were sold and the sales were $2495, how many of the $87 radios were sold a) 5 b) 20 c) 15 d)10

Find the slope and the y-intercept if there's one and the equation of the line given these two points( 3, 2) and( 3, -4)

X+y=-4 x-y=2 use elimination with adding and subtraction