Answer:
11.5
Step-by-step explanation:
using Pythagoras theorem
the square of 13 equals the square of 6 and the unknown side
Translating into a mathematical equation:
n + n^2 = 72
Rewriting, n^2 + n - 72 = 0
Factoring, (n+9)(n-8) = 0
Solving for n: n = -9 or n = 8
You must check both answers before accepting one, the other or both.
Example: suppose we check out n = 8. Then 8 + 8^2 = 72 is true, and n = 8 is a solution. Is n = -9 a solution? Try it.
Not easy to graph but
multily first equaiton by -2 remember to flip sign
-2x+4y>-6
add to other equaiton
2x-2x+y+4y>-6+8
5y>2
divide by 5
y>2/5
subtitute
2x+2/5>8
subtract 2/5 from both sdies
2x>7 3/5
divid eby 2
x>38/10=19/5=3 4/5
x>3 4/5
y>2/5
just shade the area in that zone, not including point (0,0)
33333333333333333333333333333333333
