Answer:
D..... 3 lines of Symmetry
when i calculated the ans came as 20.83333333
just cross verify it but from 21 papers 126 tickets can be made
If they have the same measure two circles are congruent if they have the same diameter
The best method for solving # 1 is substitution
x - 0.9y = 4.5......x = 0.9y + 4.5
now sub 0.9y + 4.5 in for x in the other equation
1.5(0.9y + 4.5) - 1.9y = -29 ----distribute through the parenthesis
1.35y + 6.75 - 1.9y = -29
1.35y - 1.9y = -29 - 6.75
-0.55y = -35.75
y = -35.75 / -0.55
y = 65
x - 0.9y = 4.5
x - 0.9(65) = 4.5
x - 58.5 = 4.5
x = 4.5 + 58.5
x = 63
solution is (63,65)
The best method for solving # 4 is by elimination
14x + 7y = 217
14x + 3y = 189...multiply by -1
-----------------
14x + 7y = 217
-14x - 3y = -189 (result of multiplying by -1)
----------------add
4y = 28
y = 28/4
y = 7
14x + 7y = 217
14x + 7(7) = 217
14x + 49 = 217
14x = 217 - 49
14x = 168
x = 168/14
x = 12
solution is (12,7)