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Solve the quadratic equation, x^2 - 4x -5 = 0

Solve x²- 4x - 5 = 0
A very full explanation would be:
Start by listing the pairs of numbers that can be multiplied together to get 1 * -5 = -5 (i.e. the coefficient of the first ter...

Answered by Ryan H. • Maths tutor

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Solve for y and x, where x=y+1 and y=2x+3

Simultaneous equations:
x=y+1 y=2x+3
First solve for x. y=2x+3 so first equation becomes: x=(2x+3)+1 x-2x-3-1=0 -1x-4=0x+4=0 x=-4
Solve for y: y=2x+3 y=2(-4)+3 y=-8+3y=-5

Answered by Tom S. • Maths tutor

3437 Views

Solve the simultaneous equations 2x + y = 7 and 3x - y = 8

There are three methods for solving simultaneous equations: elimination, substitution and by using graphs.Elimination is a good method in this case as the y terms are equal in both equations. We just add ...

Answered by Tia J. • Maths tutor

6670 Views

Prove the change of base formula for logarithms. That is, prove that log_a (x) = log_b (x) / log_b (a).

Firstly, recall the definition of a logarithm: if y = log_a(x), then this means that y is the power you have to raise a to, to get x, that is a^y = x.Now, we want to introduce a new ba...

Answered by Tom H. • Maths tutor

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