X - y + x + y = 180
2x = 180
x = 90
2x - 2y = x + y
x = 3y
y = x/3
y = 90/3
y = 30
x - y = 90 - 30 = 60
x + y = 90 + 30 = 120
2x - 2y = 180 - 60 = 120
the answer for 135 times 12 is 1620
Place value of 4 is 4/100
Six multiplied by three equals eighteen. fifteen plus three equals eighteen. and eighteen equals eighteen. therefore the equation is equal, because everything in the equation equals eighteen. Good Luck ;)