Answer:
33
Step-by-step explanation:
To evaluate f(- 3) substitute x = - 3 into f(x)
f(- 3) = - (- 3)³ + (- 3)² + (- 3) = - (- 27) + 9 - 3 = 27 + 9 - 3 = 33
3x = -5y -------------- (1)
6x - 7y = 17 --------- (2)
From (1):
3x = -5y
x = -5/3 y ---------- sub into (2)
6 (-5/3 y) - 7y = 17
-10y - 7y = 17
-17y = 17
y = -1 ------------ Sub into (1)
3x = -5 (-1)
3x = 5
x = 5/3
Ans: x = 5/3, y = -1
Answer:
x = 11.5
Step-by-step explanation:
Taking the logarithm base 2 will transform this to a linear equation.
2(2x+7) = 3(2x -3)
0 = 3(2x -3) -2(2x +7) . . . . subtract the left side
0 = 2x -23 . . . . . . . . . . . . . simplify
0 = x - 23/2 . . . . . . . . . . . . divide by 2
11.5 = x . . . . . . . . . . . . . . . . add 11.5
The solution is x = 23/2 = 11.5.
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<em>Check</em>
This value of x makes the equation become ...
4^(2·23/2 +7) = 8^(2·23/2 -3)
4^30 = 8^20 . . . . . true
I think you're having trouble because the equation you wrote for 8a has a slight typo.
The question says that the length is 9 less than twice the width. Your equation states the length is 9 times the width minus 2. So the length actually equals 2w – 9, meaning that w(2w – 9) = 180
Hope this helps! If you're still having trouble, let me know :)
