4a + 2c = 70 ; a = 14 ; c = 7 ; 4(14) + 2(7) = 70 ; 56 + 14 = 70 ; 70 = 70
8a + 12c = 196 ; 8(14) + 12 (7) = 196 ; 112 + 84 = 196 ; 196 = 196
Get the value of a:
4a + 2c = 70
4a = 70 - 2c
4a/4 = (70 - 2c) / 4
a = (70 - 2c) / 4
Substitute the value of a:
8a + 12 c = 196
8 ((70 - 2c)/4) + 12c = 196
(8*70)/4 - (8*2c)/4) + 12c = 196
(560 / 4) - (16c / 4) + 12c = 196
140 - 4c + 12c = 196
-4c + 12c = 196 - 140
8c = 56
8c / 8 = 56 / 8
c = 7
a = (70 - 2c) / 4
a = ((70 - 2(7))/4
a = (70 - 14)/4
a = 56 / 4
a = 14
Radius is 8
diameter is 16
curcumference is 50.24
