Solve the following equation. 7x^2 = 13x +2
First gather all x terms on left hand side,7x2-13x-2=0.
Since 7 is a prime number we can begin factorisation,(7x+/-?)(x+/-?)=0.
We know there must be a +/-2 and +/-1 in place of the question mark as they must multiply to make -2, so from the FOIL method, we can see,(7x+1)(x-2)=0 is the correct factorisation.
Then for the left bracket to equal 0, 7x+1=0 so 7x=-1 then x=-1/7.For the other solution, x-2=0 so x=2.
Therefore the two solutions are x= -1/7 or 2.
LS
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