How do you solve the simultaneous equation, 7x – 20 = 3x + 4?

To solve this equation we want to find the value of one unknown, x. The solution will be x = ___. So first we need to put all the terms with x on one side of the =, and all the constants on the other side. To balance the equation, any operation we do, we have to do to both sides I would start by subtracting 3x from both sides, 7x – 20 – 3x = 3x + 4 -3x, 4x – 20 = 0 + 4 Then I would add 20 to both sides 4x – 20 + 20 = 4 +20, 4x = 24 Finally, to find the value of x, I would divide both sides by 4 x = 24

AA

Related Maths 11 Plus answers

All answers ▸

Jack can paint a house in 5 days, and Richard can paint the same house in 7 days. Working together, how long will it take them to finish the job?


There are 45 pupils in a class, 1/9 travel to school by train, 2/5 travel to school by car, 2/9 take the bus. Find how many students walk


There are 2 green jelly beans, 5 are yellow and 13 are red. Sue picks one jelly bean. What is the possibility that sue pick a jelly bean that is not yellow?


The average temperature in May is 18 ºC. The average temperature in November is a third of the average temperature in May. The average temperature in September is twice the average temperature in November. What is the average temperature in September?