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### Course: Get ready for 8th grade>Unit 2

Lesson 1: Algebraic equations basics

# Testing solutions to equations

A solution to an equation makes that equation true. Learn how to test if a certain value of a variable makes an equation true.

## Want to join the conversation?

• i think all this math is hurting my head
• ugh... same here i need a math buddy to help me
• Help! When I attempted to solve for x, I got 5x is equal to 4x. Here's how I did it.
5x-3=4x+3. -3 and +3 cancel out to 0, so I am left with5x=4x.
• 5x-3=4x+3
5x=4x+6
x=6

Be careful with the signs of the constants or variables. The 3s definitely do NOT "cancel out." First I added 3 to both sides, then I subtract 4x from both sides. Hope this helps.
• So i did the equation, but im not sure i did it right.
5x-3=4x+3
+3 +3
5x = 4x+6
-4x -4x
x=6
Is this the right way to do it?
• Yes. As shown in this video, you can also check your answer by substituting it back into the original equation. Simplify both sides and make sure they are equal.

5(6)-3 = 4(6)+3
30-3 = 24+3
27 = 27
They are equal, so you have a good solution.
• He makes everything look so easy
• this is hard
HOW DO I BEAT THIS
• bro this isnt a video game 💀
• 7+5(x-3)=22 if x=4,5,6 and 7 which is correct and could you give me an example
• I'll do the 4 as an example:
1) Swap out "x" and replace it with the given value: 7 + 5(4 - 3) = 22
2) Follow order of operations rules (PEMDAS) to simplify the left side
-- Do the work inside the parentheses: 7 + 5(1) = 22
-- Multiply: 7 + 5 = 22
-- Add: 12 = 22
3) Are the 2 sides equal? No. This means 4 is not a solution to the equation. If the 2 sides are equal, then the number would be a solution.

Hope this helps.
• I think your videos make my head spin and I have an A in math plus the highest A in the class. You need to just slow down and stop making people have to pause the video
• that's a bit funny
(1 vote)
• i aint readin allat ( i am )