Answer:
none
Explanation:
None of the expressions should have an equal sign.
A. 7 + 3 x 6 - 4 = 7 + 18 - 4 = 25 - 4 = 21
B. 70 - 5 = 3 + 8
If = should be -
70 - 5 - 3 + 8 = 65 - 3 + 8 = 62 + 8 = 70
If = should be +
70 - 5 + 3 + 8 = 65 + 3 + 8 = 76
C. 42 = (6 x 8)
If = should be -
42 - (6 x 8) = 42 - 48 = -6
If = should be +
42 + (6 x 8) = 42 + 48 = 90
D. 60 - (12 = 4 + 1)
If = should be -
D. 60 - (12 - 4 + 1) = 60 - (8 + 1) = 60 - 8 = 51
If = should be +
D. 60 - (12 + 4 + 1) = 60 - (16 + 1) = 60 - 17 = 53
None of the expressions equal 56 even when substituting plus or minus for the equal signs.