My little bro need help 7th grade math
4( ?m - ?n)
8m - 20n

Which equation results from adding the equations in this system? x+6y=9 and -x+2y=-15

Let u = {q, r, s, t, u, v, w, x, y, z} a = {q, s, u, w, y} b = {q, s, y, z} c = {v, w, x, y, z}. list the elements in the set.a ∩ (b ∪ c)a) {q, s, w, y}b) {q, y, z}c) {q, s, u, w, y, z}d) {q, r, w, y, z}

What is the effect on the graph of the function f(x) = x2 when f(x) is changed to f(x) − 4?