Using the formula given for area:
Area = 1/2 (7 +5)4 = 1/2(12)4 = 24 square cm.
Now to find the volume multiply the area by the depth:
24 x 6 = 144 cubic cm.
3x -4 (5 - x) = 7x -20
3x-20+4x=7x-20
7x-20=7x-20
Answer:
the answer is 5+4× and ur welcome
The 2nd number line model represents 1 + ( -3 ).
I think with the kinds of mixture problems, it's really helpful to make a table.
The equations you actually need are

and

. Since I was so close, I went ahead and just solved it anyway. You can see my setup on the attached image.