Question

Please answer all and show your work thankyou

14. What is the first step to solve the equation: 8x – 3 = 21?
A. Subtract 3 from both sides B. Add three to both sides C. Divide by 8 D. Multiply by 8
15. Which of the following is equivalent to: 2(x+4) = 12?
A. 2x+4=12 C. 2x+8=12
16. 4a – 8 = 28
17. 5x – 2x = 15
18. 3(-4x + 7) = 57
19. 19 – 8x = x – 17
20. 5 + x÷8 = -4
B. 2x+8=24 D. 2x+6=12

Answer 1

Explanation:

8x-3=21

If you look through the steps, you see you are adding a value and subtracting a value which are the opposites, and the same for multiplying and dividing. It leads you on a whole spree when you can see it all cancels out, and you are left with your original. 8x-3=21

2(x+4)=12

Let's apply the distributive property.

2(x)+2(4)=12

2x+8=12
Now combine like terms for the rest to see which give you this answer.

Answer 2

14.

The answer is B. This is because you have to cancel out anything unimportant to get X alone here is the process…

8x-3= 21
8x+3=+3. {3 is now cancelled out}
8x=24
— —
8 8

x=3 (from 24/8)