Answer:
1) 9. 2) 11. 3) art and science
This is your answer ☺️☺️☺️
x+142 =3x+64
subtract x from each side
142 = 2x+64
subtract 64 from each side
142-64 = 2x
78=2x
divide by 2
78/2 = x
x=39
The number is 39
Answer:

96 people in total.
BTW its seats and I think you meant "how many"
The product of a scalar and a matrix is found by multiplying each element of the matrix by the scalar. Multiply each element by -4.
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