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You are given that (x+a)²-≡ x²+10x+b Work out the value of a and b. (2 marks) a=□ b=□

User Adzdavies
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Final answer:

The values for a and b in the equation (x + a)² = x² + 10x + b are a = 5 and b = 25, found by expanding the binomial and equating coefficients.

Step-by-step explanation:

The student is given a binomial expansion (x + a)² and is tasked with matching it to a quadratic equation of the form x² + 10x + b. To find the values of a and b, we must expand the binomial and compare the coefficients to the given quadratic equation.

Expanding (x + a)², we get x² + 2ax + a². Now, to match the given form x² + 10x + b, the coefficient of x must be 10, and the constant term must be 'b'. Hence, we equate the coefficients: 2ax = 10x, which simplifies to 2a = 10 by dividing both sides by x, yielding a = 5. The constant term a² must then equal 'b', meaning b = a² = 5² = 25.

User Marek Musielak
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