Radius = diameter/2 = 8/2 = 4m
Area of a circle = pi x r^2 = pi x 4^2 = 16pi m^2 ( exact area) or 50.27 m^2
Circumference = pi x diameter = 8pi m ( exact) or 25.12 m
Step-by-step explanation:
The error carolyn has made is that she hasn't subtracted properly.
2x + 3y - (2x +6y) = 2x - 2x + 3y - 6y = -3y.
Carolyn probably didn't use parentheses...
To do the thing in substitution, we single out x or y in any equation. In this case, i'm gonna single out the x in the 2nd eqn. In other words, i'll make x the subject of the 2nd eqn.
2x + 6y = 10
2x = 10 - 6y
x = 5 - 3y
Now we simply plug in 5 - 3y wherever x apperas in the 1st equation.
2 (5-3y) + 3y = 8
10 - 6y + 3y = 8
10 - 3y = 8
-3y = -2
y = 2/3
Then x = 5 - 3*2/3 = 3
x=3
y=2/3
Hope it helps:)
Answer:
Step-by-step explanation:
<em>plz mark me brainliest.</em> :)
15. [4] insufficient information. only given SA
16. There are 3 right triangles, 3 Pythagorean theorem equations
x²+b²= 16²
12²+a² = x²
a²+4² = b²
combine equations using substitution to get in terms of only x
substitute b² for (a² +x²) in first equation
x²+a²+4²=16²
substitute a² for (x² - 12²)
x²+x²-12²+4² = 16²
solve for x
2x² - 144 + 16 = 256
2x² = 256 + 144 - 16
2x² = 384
x² = 384/2
x² = 192
x = 13.85
rounded to nearest tenth, x = 13.9
