C because when you expand all the numbers, they go in the same order as c has them.
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
The linear combination method is the same as the elimination method. Let's multiply the second equation by -2 so the x terms cancel each other out. When we do that we get a system of
and
. The x-terms cancel each other out giving us
and y = -3. Now sub -3 into one of the equations to solve for x. x+2(-3)=-4, and x - 6 = -4. x = 2. So the solution for our system is (2, -3)
1.) 9 - c < 2 , C = 7
Graph 7 on the number line.
2.) -3c > 15, C = -5
Graph -5 on the number line.
Hope this helps.
