Answer:
a.0.126
b.100.6356
c.5.010
Step-by-step explanation:
This is an isosceles right triangle (AB = BC & ∠ B=90° - Given)
Then the angles at the base are equal and ∠ CAB = ∠ ACB = 45°
Theorem: Segment DE, joining the midpoints of 2 sides is:
1st) parallel to the 3rd side and
2nd) equal to half the measurement of the 3rd side
So if the 3rd side (hypotenuse) = 9 units, DE = 9/2 = 4.5 units
Assuming you mean y=10x+150 and y=20x+115, you need to use a simultaneous equation, because you have two equations with two unknowns (x and y)
rearrange so
10x-y=-150
20x-y=-115
multiply the top by -1, so that if we add the two lines together, the y will cancel out
-10x+y=150
20x-y=-115
add the two lines together
10x=35
x=3.5
so the time is 3 and a half weeks
then we can sub in x to find y
20x-y=-115
20(3.5)-y=-115
70-y=-115
-y=-185
y=185
so 185 tickets were sold !
you can sub these values into your original equations to check your answer :)
A) The result of adding the two equations is
.. (2.5y +3x) +(5x -2.5y) = (27) +(5)
.. 8x = 32 . . . . . . . . . . . . . . . . . . . . . . . your 2nd selection
b) The solution to the system is (4, 6), your 4th selection.
.. This is the only choice with x=4, the solution to part (a).