C = child tickets
a = adult tickets
Solve this with the substitution method.
Make two equations:
6.30c + 9.90a = 1,246.50
c + a = 159
Solve for c.
Subtract 9.90a from both sides.
6.30c = 1,246.50 - 9.90a
Divide both sides by 6.30.
c = 197.86 - <span>1.57a (rounded to hundredths)
Plug c into second equation.
</span>197.86 - 1.57a + a = 159
Combine like terms.
197.86 - 0.57a = 159
Subtract 197.86 from both sides.
-0.57a = -38.86
Divide both sides by -0.57.
a = <span>68.18
round up to ones: 68
</span>

were sold.<span>
</span>
Answer:
x = 9/4
Step-by-step explanation:
f(x) = 4x - 9
(first substitute f(x) with 0)
0 = 4× - 9
(Move four)
-4x = -9
=> x = -9/-4
= 9/4
Answer:

Step-by-step explanation:
For every
of television time of commercials = 
% of commercials 
Now when time of television

Answer:
36 meters
Step-by-step explanation:
The bird starts at 20 and (assuming it goes up) increases by 16 meters. You have to add to get 36. However, if the bird flies 16 meters down, the answer would be four meters. The answer 36 is assuming the bird flies upward.
Measure of the interior angle: 180 -113: 67
the measure of interior angle is 67.