Solve 7(x+2)=5x+21

The first thing we must realise is that there are brackets in this equation and thus this has to be dealt with. We expand out the brackets on the left side by multiplying 7 by x and 2 to obtain '7x+14'. We now have the equation '7x+14 = 5x +21'. We have to collect the x terms on one side, preferably the left hand side, and the other constants on the other side. Subtracting 5x from both sides, we get '2x+14 = 21'. We repeat the same by subtracting 14 from both sides to get '2x = 7'. To find the solution to this equation we have to find out the value of x and thus if we divide both sides by 2 we get the final solution, x=3.5 or 7/2

Related Maths GCSE answers

All answers ▸

(x+6) and (x+5) are the length and width, respectively, of a rectangle with area 20. Calculate the width of the rectangle.


Solve the simultaneous equations (1) 2a - 5b = 11 (2) 3a + 2b = 7


Solve 3x^2+7x-13=7 to find x.


Sarah asked 20 people at a tennis tournament how they travelled there. She found that 13 of them travelled by car. Estimate how many of the total 2000 people at the tournament travelled by car.