Question

1. -2x + 9x - 15 - 4x

3x - 15
follow the order of operations and simplify.

1. 15 - 2×6 + 8÷4

15 - 12+8÷4
find the error and circle it. what is the mistake? explain.
-8x + 5x - 3x + 4 - 6x + 7
-3x - 3x + 4 - 6x + 7
-6x + 4 - 6x + 7
-12x + 11
use complete sentences to explain the mistake.
can you combine 4x and 7? why or why not? explain.
answer:
bonus - solve the equation for x:

1. 9x + 2(5x - 3)= -25

9x+10x - 6
explain in your own words how you would simplify the following expression.

1. -3(x - 7)+2x

Explanation:

Step1: Simplify -2x + 9x - 15 - 4x

Combine like - terms: (-2x+9x - 4x)-15 = 3x - 15

Step2: Simplify 15 - 2×6+8÷4

First, perform multiplication and division: 2×6 = 12 and 8÷4 = 2. Then the expression becomes 15-12 + 2. Then perform addition and subtraction from left - to - right: 15-12=3, and 3 + 2 = 5. The error in the given work is that 8÷4 was calculated as 4 instead of 2.

Step3: Analyze -8x + 5x - 3x+4 - 6x + 7

Combine like - terms: (-8x+5x - 3x-6x)+(4 + 7)=(-8 + 5-3 - 6)x+11=-12x + 11. There is no error in this simplification.

Step4: Answer if 4x and 7 can be combined

No, 4x and 7 cannot be combined because 4x is a term with a variable x and 7 is a constant. Only like terms (terms with the same variable(s) raised to the same power(s)) can be combined.

Step5: Solve 9x+2(5x - 3)=-25

First, use the distributive property: 9x+10x-6=-25. Then combine like - terms: (9x + 10x)-6=-25, 19x-6=-25. Add 6 to both sides: 19x-6 + 6=-25 + 6, 19x=-19. Divide both sides by 19: x=-1.

Step6: Simplify -3(x - 7)+2x

Use the distributive property: -3x+21 + 2x. Then combine like - terms: (-3x+2x)+21=-x + 21.

Answer:

1. 3x - 15; 12) The correct answer is 5, the error was calculating 8÷4 as 4 instead of 2; 13) x=-1; 14) -x + 21; 4x and 7 cannot be combined because they are not like terms.