His mistake was adding 12+2 when he was supposed to subtract.
You would do
51-5= 46
then you would divide
46/2= 23
so Susan is
23+5=28
Susan is 28 years old and her sister is 23
28+23=51
Answer:
c=3
Step-by-step explanation:
Angle sum of a triangle is 180°
(19c+16)°+13c°+(17c+17)°=180°
collect the like terms i.e
19c+13c+17c+16+17=180°
49c°+33°=180°
49c°=180°-33°
49c°=147
dividing by 49 both sides
49c/49=147/49
c=3
Answer:
x = 30
Step-by-step explanation:
1/2(x+6) = 18
Distribute
1/2 x + 3 = 18
Subtract 3 from each side
1/2x +3-3 = 18-3
1/2x = 15
Multiply each side by 2
1/2x*2 = 15*2
x = 30