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Using the "complete the square" method, solve the following x^2 +4x - 21 =0

x²+4x-21= 0, This can be factorised into brackets as shown: (x+2)²- 4 - 21 = 0 SImplified, so all x's are on one side of the equation: (x+2)²= 25, Removing square root, DONT FORGET "±" : (x+2) = ± 5, Solve for two solutions: x = 3, x = -7

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Using the "complete the square" method, solve the following x^2 +4x - 21 =0

Related Maths A Level answers

What are complex and imaginary numbers and how are they different from normal (real) numbers?

Determine the tangent to the curve y = sin^2(x)/x at the point, x = pi/2. Leave your answer in the form ax+by+c=0

Find dy/dx in terms of t for the curve defined by the parametric equations: x = (t-1)^3, y = 3t - 8/t^2, where t≠0

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We're here to help

Company Information

Popular Requests

© MyTutorWeb Ltd 2013–2024

CLICK CEOP

let p be a polynomial p(x) = x^3+bx^2+ cx+24, where b and c are integers. Find a relation between b and c knowing that (x+2) divides p(x).