9514 1404 393
Answer:
3a by 4a
Step-by-step explanation:
For dimensions L and W, the area and perimeter are ...
A = LW = 12a^2
P = 2(L+W) = 14a
Using the second equation, we can find L:
L +W = 7a . . . . . divide by 2
L = 7a -W
Substituting into the area formula gives the quadratic ...
(7a -W)(W) = 12a^2
W^2 -7aW +12a^2 = 0 . . . . arrange in standard form
(W -3a)(W -4a) = 0 . . . . . . . factor (find factors of 12 that total 7)
Then we have the two solutions ...
W = 3a, L = 4a
W = 4a, L = 3a
The rectangle dimensions are 3a by 4a.
If AC=BD, than Quad ABCD is a rectangle
AC
√(3+3)²+(6-1)²
√6²+5²
√36+25
√61
BD
√(1+1)²+(2-7)²
√2²+(-5)²
√4+25
√29
Quad ABCD is not a rectangle because √61 and √29 are not equal.
Answer:
111°
Step-by-step explanation:
- All these are parallel lines, so the 36° angle is equal to the 36° angle inside the big triangle because they are vertically opposite.
- Ignore the line cutting between 45° and the 30° and consider it as one triangle
- Add them to get 75°
- Now you have two known angles 75° and 36°
- To get angle <em>x</em><em> </em>add 75° and 36° to get 111°
- Because x° is an exterior angle and exterior angles equal to the sum of interior angles opposite it inside the triangle.
Class of students - number of students that are boys = numbers of students that are girls
30 - 13 = 17
To change the number of students that are girls into percentage...
17/1 * 1/100 = 17/100
17/100 in a % form = 17%
The percentage of girls in the class is 17%
Answer:
D
Step-by-step explanation:
The sum of two remote interior angles (a remote interior angle is the interior angle that is not supplementary to the exterior angle given -- in this case A and B are remote angles) equals the exterior angle.
In This case A + B = 140
A = x + 2
B = 2x
x +2 + 2x = 140
3x + 2 = 140 Subtract 2 from both sides
3x = 138 Divide by 3
x = 138/3
x = 46
<B = 2x
<B = 2*46
<B = 92
