



 
Hi Destiny, Let me try a similar problem.
In evaluating this expression I need to perform the operations inside the parentheses first so I need to evaluate $7  4x$ when $x = 3.$ Substituting $x = 3$ into $7  4x$ gives me $7  (4 \times (3)) = 7  (12) = 7 + 12 = 19.$ Hence the expression becomes \[5x + (7  4x) = 5 \times (3) + 19 = 15 + 19 = 4.\] Now try your problem and write back if you need more help. Penny  


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