x2+7x+10 = 0 factorise this into the form (x+a)(x+b)=0 by finding out what 2 numbers multiply to make 10 and add up to 7. the 2 numbers that fit this criteria are 5 and 2 so (x+5)(x+2)=0, if we expanded these brackets we would have the original quadratic equation we are solving. so because the quadratic equation has to equal 0 this means either x+5=0 or x+2=0 finally we have to solve what is x is but getting it on its own for example x+5=0, to get x on its own we minus 5 but we have to do the same on the other side of the = sign so x=-5 then we do the same for x+2=0 so x=-2 our final answer: x= -5 or x= -2