Consider this equation.
7.8 + 2(0.75m + 0.4) = -6.4m + 4(0.5m - 0.8)
mia solved the equation and determined that m = 2. is she correct?
a. she is incorrect because when substituting 2 for m the result was a true statement.
b. she is incorrect because when substituting 2 for m the result was a false statement.
c. she is correct because when substituting 2 for m the result was a true statement.
d. she is correct because when substituting 2 for m the result was a false statement.

B if m=2

(Just to make sure that isn't m=-2, right?)

Step-by-step explanation:

7.8 + 2(0.75m + 0.4) = -6.4m + 4(0.5m - 0.8)  

Let's plug in 2 for m.

7.8+2(0.75*2+0.4)  = -6.4*2+4(0.5*2-0.8)

If 2 is a solution, then both sides will be the same.

If 2 is not a solution, then both sides will be different.

If both sides are the same, it is a true equation.

If both sides are different, it is a false equation.

Let's simplify 7.8+2(0.75*2+0.4)

According to PEMDAS, we must perform the operations in the parenthesis.

We have multiplication and addition in ( ).  We will do the multiplication because the MD comes before the AS.

0.75*2=1.5

So now our expression 7.8+2(0.75*2+0.4) becomes 7.8+2(1.5+0.4)

Now to do the addition in the ( ).

1.5+0.4=1.9.

So now our expression 7.8+2(0.75*2+0.4) becomes 7.8+2(1.9).

We have multiplication to be perform now because again MD becomes before AS.

7.8+2(0.75*2+0.4) becomes 7.8+3.8

Last step perform the addition (the only operation left here on the left hand side)

7.8+2(0.75*2+0.4) becomes 11.6 .

Let's focus on the right now.

-6.4*2+4(0.5*2-0.8)

-6.4*2+4(1       -0.8)  I did the multiplication in the ( ) first.

-6.4*2+4(.2)              I did the subtracting in the ( ).

-12.8+.8                    I did the multiplication by -6.4*2 and 4*.2 simultaneously

-12

I'm going to put all of this together because I think it might be easier to read:

7.8 + 2(0.75m + 0.4) = -6.4m + 4(0.5m - 0.8)  

Plug in 2 for m

7.8 + 2(0.75*2  + 0.4)=-6.4*2 + 4(0.5*2 - 0.8)

7.8 + 2(1.5        + 0.4)= -6.4*2 + 4(1       -0.8)

7.8 + 2(1.9)                = -6.4*2 + 4(.2)

7.8 +  3.8                 =   -12.8  +.8

11.6                          =-12

This is false because 11.6 is not the same as -12.

m=2 leads to a false equation

B.

a. 74 degrees

step-by-step explanation:

because the lines through the side and the box in the corners shows that these are congruent triangles and since they are mirrored the 37 degrees is also mirrored so the answer is 37 * 2 which is 74.

what is the approximate angle of acb if abc is 25cm and the length of segment bc is 15

step-by-step explanation: