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How to complete the square to solve quadratic equations?

Equation: x²+4x-5=0 (This is in the form ax²+2bx+c=0)First divide 2b by 2 (4/2=2)Then put this into (x+b)²-(b)²+c=0This gives: (x+2)²-(2)²

Answered by George J. • Maths tutor

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Write 16× 8^2x as a power of 2 in terms of x.

16 = 2⁴8^2x = (2³)^2x = 2^6xTherefore, 16x8^2x = 2⁴x 2^6x = 2^4+6x

Answered by Xixi Y. • Maths tutor

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Solve the following simultaneous equations: x^2 + 2y = 9, and y = x + 3.

Label the two equations as the following: x² + 2y = 9 y = x + 3 Equation 2 can be substituted into equation 1, giving: x² + 2( x + 3 ) = 9Expanding the brackets and subtracting ...

Answered by Ximena B. • Maths tutor

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How do I solve simultaneous equations by substitution?

You can solve simultaneous equations by either substitution or elimination. Say we have the equations:(1) 8y + 6x = 24 and (2) 2y - x = 6SUBSTITUTION METHODFirst, you need to find x in terms of y (or y in...

Answered by Joshua N. • Maths tutor

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Simplify the following, 125^-2/3

1. The minus sign indicates that the answer is a reciprocal meaning basically 1 over.2. Next, on inspection of the fraction, the 2 on top means that you square the number, times it by itself...

Answered by Cameron B. • Maths tutor

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