Solve the following to find x. x^2 +3x -10 =0
This is an example of a quadratic equation. One way of solving it wwould be to use the quadratic formula. You can subsitute the values of a, b and c into the formula where a=1 b=3 and c=-10. This will give 2 values of x.
Another way which is much faster is to start by factorising the left hand side.
This is done by finding two numbers that add up to make 3 and mutliply together to make -10.
In this case those numbers are 5 and -2.
So a factorised version of x2+3x -10=0 is
(x-2)((x+5)=0
In order to find x we need to find the values where each set of brackets is equal to zero. This is because anytthing multiplied by zero is equal t0 zero. So if the value of the inside of one bracket is equal to zero the whole left hand side is equal to zero.
Therefore x=-5 and x=2
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