Solve the equation 3(x+1) = 21

When solving an equation with brackets, it is often easiest to expand the brackets first.3(x+1) = 21becomes...3x + 3 = 21Now this looks like an equation we know how to solve(minus three from both sides)3x + 3 - 3 = 21 - 3becomes...3x = 18divide both sides by 3...x = 6

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Answered by James M. Maths tutor

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