Answer:
X = 116
Step-by-step explanation:
Total heptagon angle = 900
124 + 120 + 122 + 136 + 144 + 138 = 784
900 - 784 = 116
f(g(-1)) = - 3
Evaluate g(-1) and substitute into f(x)
g(-1) = (-1)² -7(-1) - 9 = 1 + 7 - 9 = - 1
f(g(-1)) = (-1) - 2 = - 3
Multiply 2x-5y= -21 by 3 to make it 6x-15y= -63
Multiply 3x-3y= -18 by -5 to make it -15x+15y=90
This cancels the y’s out which leaves us with
6x=-63
&
-15x=90
x for 6x=-63 equals - 10.5 so x is - 10.5 and for -15x=90, x= -6
Then you plug in x into any equation you’d like to find y.
Let’s plug in - 10.5 into 6x... equation.
6(- 10.5)-15y=-63
63-15y= -63
-63 -63
-15y=0
y=0 and x= - 10.5. When you plug in this values it makes the equation true!
But the correct answer is the first one north. Sorry if I’m doing too much hahah
If I’m confusing here’s the right answer...
6x-15y= -63
-15x+15y=90
1 hour = 60 minutes, so 3 hours = 3 * 60 = 180 minutes.
Her total time was 3 hours and 28 minutes, so 180 + 28 = 208 minutes.
Divide her total time by total miles run:
208 minutes / 26 miles = 8 minutes per mile.
