Answer:
30
Step-by-step explanation:
To find the determinant of a 3x3 matrix, you can use this method. (See picture.)
Start with the first number in the top row, and block off the row and column. A 2x2 matrix will be left. Find the determinant of this 2x2 matrix, and multiply it by the number in the top row.
Repeat for the other two numbers in the top row. Add the first result, subtract the second, and add the third.
det A = -2 [(3)(-5) − (a)(0)] − 2 [(0)(-5) − (a)(0)] + b [(0)(0) − (3)(0)]
det A = -2 (3)(-5) − 0 + 0
det A = 30
Answer:
Equation:(4 2/5)/2/5=? ; estimate: a
little more than 10 magazines; answer:
11 magazines in the stack.
Step-by-step explanation:
Since TSQ and QSR are supplementary, they give 180 when summed. TSQ is 150, so QSR must be 30.
Therefore, you have

Answer:
x=1, y=1. (1, 1). The answer is D).
Step-by-step explanation:
3x-5y=-2
4x-7y=-3
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4(3x-5y)=4(-2)
-3(4x-7y)=-3(-3)
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12x-20y=-8
-12x+21y=9
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y=1
3x-5(1)=-2
3x-5=-2
3x=-2+5
3x=3
x=3/3
x=1