Cos (B) = (a^2 + c^2 -b^2) / (2 * a * c)
cos (B) = (11^2 +17^2 -12^2) / (2 * 11 * 17)
cos (B) = (121 + 289 -144) / (374)
cos (B) = 266 / 374
cos (B) =
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0.7112299465
Angle B = </span></span></span>44.665 degrees
20 * 4 = 80 = perimeter of the square 24*2 = 48, the length of two sides of the rectangle. Deducting from 80 we are left with 32 and dividing by 2 we know the rectangle is 24 x 16 Area = L * W, so you can calculate the area of the rectangle.
384
The answer would be x ≠ 0
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First start with the left side, doing distributive property
So... -2(x) = -2x and -2(5) = -10 Therefore on the left side you now have -2x -10
Next do the same on the right side
-2(x) = - 2x and -2(-2) = 4 so you have -2x + 4 + 5 and you add 4 and 5, leaving you with -2x + 9
Now that you have simplified both sides the problem now looks like this:
-2x - 10 = -2x + 9
Because you have equal terms on both sides (-2) those cancel out so you have -10 = 9
Just from looking at this we know that the statement is false because -1o does not equal 9
*The symbol, "≠" means not equal to"
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
For this case, what we must do is fill squares in all the expressions until we find the correct result.
We have then:
x2 + y2 − 4x + 12y − 20 = 0 x2 + y2 − 4x + 12y = 20
x2 − 4x + y2 + 12y = 20
x2 − 4x + (12/2)^2 + y2 + 12y + (-4/2)^2 = 20 + (12/2)^2 + (-4/2)^2
x2 − 4x + (6)^2 + y2 + 12y + (-2)^2 = 20 + (6)^2 + (-2)^2
x2 − 4x + 36 + y2 + 12y + 4 = 20 + 36 + 4
(x − 2)2 + (y + 6)2 = 60
3x2 + 3y2 + 12x + 18y − 15 = 0
x2 + y2 + 4x + 6y − 5 = 0
x2 + y2 + 4x + 6y = 5
x2 + 4x + (4/2)^2 + y2 + 6y + (6/2)^2 = 5 + (4/2)^2 + (6/2)^2
x2 + 4x + (2)^2 + y2 + 6y + (3)^2 = 5 + (2)^2 + (3)^2
x2 + 4x + 4 + y2 + 6y + 9 = 5 + 4 + 9
(x + 2)2 + (y + 3)2 = 18
2x2 + 2y2 − 24x − 16y − 8 = 0
x2 + y2 − 12x − 8y − 4 = 0
x2 + y2 − 12x − 8y = 4
x2 − 12x + (-12/2)^2 + y2 − 8y + (-8/2)^2 = 4 + (-12/2)^2 + (-8/2)^2
x2 − 12x + (-6)^2 + y2 − 8y + (-4)^2 = 4 + (-6)^2 + (-4)^2
x2 − 12x + 36 + y2 − 8y + 16 = 4 + 36 + 16
(x − 6)2 + (y − 4)2 = 56
x2 + y2 + 2x − 12y − 9 = 0
x2 + y2 + 2x - 12y = 9
x2 + 2x + y2 - 12y = 9
x2 + 2x + (2/2)^2 + y2 - 12y + (-12/2)^2 = 9 + (2/2)^2 + (-12/2)^2
x2 + 2x + (1)^2 + y2 - 12y + (-6)^2 = 9 + (1)^2 + (-6)^2
x2 + 2x + 1 + y2 - 12y + 36 = 9 + 1 + 36
(x + 1)2 + (y − 6)2 = 46
