(7TH GRADE LEVEL) Read the instructions and answer questions 16-18

Equations

Step-by-step explanation:

16:

7 · (-3) = -21

-3 · 7 = -21

-21 ÷ 7 = -3

-21 ÷ (-3) = 7

17:

-4 · (-5) = 20

-5 · (-4) = 20

20 ÷ (-4) = -5

20 ÷ (-5) = -4

18:

1.5 · (-3) = -4.5

-3 · 1.5 = -4.5

-4.5 ÷ 1.5 = -3

-4.5 ÷ (-3) = 1.5

This is 7th grade?

Hope I helped :)

16. 7 x -3= -21

    -3 x 7= -21

    -21/-3=7

    -21/7=3

17. -4 x -5= 20

    -5 x -4= 20

    20/-4=-5

    20/-5=-4

18. 1.5 x -3= -4.5

   -3 x 1.5=-4.5

   -4.5/-3=1.5

   -4.5/1.5=-3

Step-by-step explanation:

multiplication and division

answerthe vertex form

step-by-step explanation:

starting with:    

5 + x - 12 = 2x - 7   

5 + x - 12 - x = 2x - 7 - x (subtract x from both sides)   

5 - 12 = x - 7 (combine and cancel x's from both sides)   

5 - 12 + 7 = x - 7 + 7 (add 7 to both sides)   

0 = x (add numbers together on both sides)       

so in order for the equation to be true, x must be 0.   

trying x = -0.5   

5 + x - 12 = 2x - 7 (original equation)   

5 + -0.5 - 12 = 2(-0.5) - 7 (plug in value of x)   

5 + -0.5 - 12 = -1 - 7 (did multiplication)   

-7.5 = -8 (did addition on both sides)       

since -7.5 is obviously not equal to -8, the value of -0.5 for x is wrong.   

trying x = 0   

5 + x - 12 = 2x - 7 (original equation)   

5 + 0 - 12 = 2(0) - 7 (plug in value of x)   

5 + 0 - 12 = 0 - 7 (did multiplication)   

-7 = -7 (did addition on both sides)       

since -7 equals -7, that demonstrates that the value of 0 for x is correct.   

trying x = 1   

5 + x - 12 = 2x - 7 (original equation)   

5 + 1 - 12 = 2(1) - 7 (plug in value of x)   

5 + 1 - 12 = 2 - 7 (did multiplication)   

-6 = -5 (did addition on both sides)       

since -6 is obviously not equal to -5, the value of 1 for x is wrong.