Answer:
The angles are 15 degrees, 45 degrees and 120 degrees
Step-by-step explanation:
The triangle has three three sides and three angles. The sum of the angles in a triangle is 180 degrees
Let x = the size of the largest angle of the triangle
Let y = the size of the middle angle of the triangle
Let z = the size of the smallest angle of the triangle.
x + y + z = 180 - - - - -- - - - - - - 1
The size of the largest angle is eight times the size of the smallest angle.
This means
x = 8z
The size of the middle angle is triple the size of the smallest angle. This means
y = 3z
Put x = 8z and y = 3z in equation 1
8z + 3z + z= 180
12z = 180
z = 180/12 = 15
x = 8z = 8×15 = 120
y = 3z = 3 × 15 = 45
Answer: B) Circle
<u>Step-by-step explanation:</u>
First, complete the square:
x² + 2x + <u> 1 </u> + y² - 8y + <u> 16 </u> = 13 + <u> 1 </u> + <u> 16 </u>
↓ ↑ ↓ ↑
(2/2) = (1)² (-8/2) = (-4)²
(x + 1)² + (y - 4)² = 30
The result is a circle whose center is (-1, 4) and radius is √30
Answer:
He made a mistake in his calculations when simplifying 5x - 2y
Step-by-step explanation:
Given
The coordinate pair

The equations


Dimitri's Solution








Required
Identify Dimitri’s mistake
In the first equation, Dimitri made no mistake.
However, he made a mistake when simplifying the second equation.
We have:

and

Substitute
and 
So, we have:

Open bracket

Finally, we have:

Answer:
n = -1
Step-by-step explanation:
1 - 8n - 8 = -7n - 6n - 12
Simplify
-8n - 7 = -13n - 12
Add 7 to both sides
-8n = -13n - 5
Add 13n to both sides
5n = -5
Divide both sides by 5
n = -1