$8 + $7 + $13 + 15 = $43
$x - $43 = $12
x = $55
i am a mathematics teacher. if anything to ask please pm me
Most of those are correct but the ones that are not are, (15+8 divided by 4-6) as division comes first. 6x3-8 as multiplication comes before subtraction. And 2/3+4x2, multiplication comes before addition. So change those couple up and you got it.