The answer is D, i.e. the system was solved via elimination
If you multiply the first equation by 5, the system becomes
If you sum the two equations, you get
And so if you substitute the second equation of system A with this new equation, you'll get system B.
Answer:
78.42
Step-by-step explanation:
Area of 360 - 80 degree region.
You need to find out the region of the major arc where the circle is almost complete. The area left over will be calculated later
Angle = 360 -80
Angle = 280 degrees.
Area =
Area =
Area = 23800/360
Area = 66.11
Area of the Triangle with sides of 5 cm each
Here's where I get into a bit of trouble. I have to assume you know some trig.
Find the height
Cos(40) = The height / the hypotenuse
Cos(40) = h/5
0.7760 = h/5
h = 0.7760*5
h = 3.830
Find 1/2 the base (the chord of the circle)
Sin(40) = 1/2 base / hypotenuse
Sin(40) = 1/2 b / 5 Multiply both sides by 5
1/2 b = 5*sin(40) Find the sin(40)
1/2 b = 5*.6428 Combine the right
1/2 b = 3.139 multiply by 2
b = 6.4278
Find the area of the triangle
Area = 1/2 b * h
b = 6.4278
h = 3.830
Area = 1/2 * 6.4278*3.830
Area = 12.31 cm^2
Total Area
12.31 + 66.11 = 78.42
