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Where does the quadratic formula come from?

The quadratic formula is used to find the roots of a quadratic equation which comes in this form: y = ax 2 + bx + c By finding the roots, we mean that we find the values of x when y equals zero. Visually, th...
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Answered by Rebecca R. • Maths tutor
3350 Views

Solve the equation p + 15 = 2(4p − 3)

Expand brackets: 8p-6. Move all values to one side: p - 8p + 15 + 6 = 0. Subtract p values and add normal numbers: -7p + 21 = 0. Move p values to other side: 21 = 7p. Divide through by 7: p = 21/7. p = 3.
LM
Answered by Luke M. • Maths tutor
5989 Views

Given that log3 (c ) = m and log27 (d )= n , express c /(d^1/2) in the form 3^y, where y is an expression in terms of m and n.

I find that a lot of maths at A-Level is unmotivated, and this causes a lot of unnecessary confusion. You can do this question, you just need to recognise the point of log and keep a level head. Log is defin...
GV
Answered by Gabriel V. • Maths tutor
4754 Views

X^2 -25 Find the solution to this equation.

candidate should recognise the equation is a difference between two squares. the next step is to factorise: square root of 25 is 5 (x-5)(x+5) = x^2-25 x= -5 x= 5
JD
Answered by Jakub D. • Maths tutor
3648 Views

If x^2 + 2y = -14 and y = 4x + 1 , by using the quadratic formula, find the possible values for x.

First the equation for y must be substituted into the first equation to give a quadratic equation in x. Rearrange this equation so that the left-hand side equals 0. Using the quadratic formula the possible v...
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Answered by Rachael W. • Maths tutor
2991 Views