Matthew has $50 in his saving, and his saving = y, y = 50
He spends $4 (the m) on snacks each time
50 = 4x + 8
Isolate the x. Note the equal sign, what you do to one side, you do to the other. Do the opposite of PEMDAS.
First, subtract 8 from both sides
50 (-8) = 4x + 8 (-8)
42 = 4x
Divide 4 from both sides
(42)/4 = (4x)/4
x = (42)/4
x = 10.5
John Matthew buys 10 snacks (since he cannot buy 1/2 a snack)
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