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When trying to solve inequalities (e.g. 1/(x+2)>x/(x-3)) I keep getting the wrong solutions even though my algebra is correct.

*The usual mistake with inequalities is not with a students algebra, but with lack of consideration of the inequality signs. During a tutorial I would show their false method and my correct one and also sket...
TH
Answered by Timothy H. • Maths tutor
4505 Views

Solve x^2 + 15x = - 50

x 2 + 15 x + 50 = 0 (rearrange by adding 50 to both sides) (x + 10)(x + 5) = 0 (factorise the quadratic equation) x + 10 = 0 or x + 5 = 0 (for the above to equal zero, at least one of the bracketed terms mus...
JS
Answered by Julia S. • Maths tutor
9895 Views

f(x) = 2x + c, g(x) = cx + 5, fg(x) = 6x + d. c and d are constants. Work out the value of d. 3 marks.

fg(x) = 2(cx+5) + c = 2cx+10+c [1 mark] fg(x) = 6x+d. fg(x) = 2cx+10+c 6x = 2cx and d = 10+c [2 marks] 3 = c and therefore d = 13 [3 marks]
HK
Answered by Heba K. • Maths tutor
22835 Views

What is the general equation for a straight graph line and what does each part represent?

Y= mX + c, 'X' is the horizontal value on the axis, the input value. The 'm' represents the gradient of the line, figured out by the change in y divided by the change in x. The 'c' value is the y intercept, ...
TW
Answered by Toby W. • Maths tutor
3635 Views

Find the range of values of x for which: x^2 + 3x + 2 < 0

If you were to factorise this quadratic to find out its roots, you would get: (x+1)(x+2) which gives us roots of -1 and -2. Remember that roots are where the graph crosses the x-axis, and are found by settin...
TN
Answered by Thomas N. • Maths tutor
6401 Views