How do i solve it by substitution? y=-24x-6y=-20

Ineed with number 6 , explain how to get 1978

Iwill give you ! what is the measure of ∠v ?

What sums are equal to 6/12? choose all answers that are correct a.6/12+6/12+6/12+6/12+6/12+6/12 b.2/12+1/12+1/12+2/12 c.5/12+1/12 d.1/12+1/12+1/12+3/12 plz : )