Question

Please help, show me the steps

Answer 1

let's say, the number is "a".

what's three times "a"? well, 3*a or 3a.

ok... what's four more than that? well, 3a + 4

what's the square root of that? well,
`\bf √(3a+4)`

alrite, and we know that's equal to 7...so


`\bf √(3a+4)=7\impliedby \textit{squaring both sides} \\\\\\ (√(3a+4))^2=7^2\implies 3a+4=49\implies 3a=45\implies a=\cfrac{45}{3} \\\\\\ \boxed{a=15}`