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
(11 + 21) - ( 3 - 100 )
= 32 + 97
= 129
or (11+21)-(3+100)
= 32 - 103
= - 71
I have no idea about your topic but hope it's right! Good luck
Hello!
Answer:
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|2x - 5| = 4
Solve for the negative and positive expressions:
2x - 5 = 4
2x = 9
x = 9/2
------------
-(2x - 5) = 4
-2x + 5 = 4
-2x = -1
x = 1/2.
Therefore, the solutions are x = 1/2 and 9/2.
Answer:
1. x =0; x = -7
2. x = -3; x = 10
3. x = -5; x = -4
Step-by-step explanation:
(1). 6x² + 42x = 0
6x (x + 7) = 0
6x = 0. OR. x + 7 = 0
x = 0/6. x = 0 - 7
x = 0. x = -7
x = 0
x = -7
(2). x² - 7x - 30 = 0
The factors here are (3, -10)
x² - 10x + 3x - 30 = 0
x ( x - 10) + 3 ( x - 10) = 0
(x + 3) ( x - 10) = 0
x + 3 = 0 OR. x - 10 = 0
x = 0-3. x = 0 + 10
x = -3. x = 10
x = -3
x = 10
(3). x² + 9x + 20 = 0
The factors are ( 4, 5)
x² + 4x + 5x + 20 = 0
x ( x + 4) + 5 ( x + 4) = 0
(x + 5) (x + 4) = 0
x + 5 = 0 . OR. x + 4 = 0
x = 0-5. x = 0 - 4
x = -5. x = -4
x = -5
x = -4
Slope = change in y/change in x.
-2-0/2-1
-2/1
-2
Final answer: -2