Question

Solve the system by substitution. Check your solution. a-1.2b=-3 0.2b+0.6a=12

Answer 1

A - 1.2b = - 3         ⇒ eq. 1
0.2b + 0.6a = 12   ⇒ eq. 2

a - 1.2b = - 3  
a = 1.2b - 3           ⇒ eq. 3

Substitute eq. 3 to eq. 2
0.2b + 0.6(1.2b - 3) = 12
0.2b + .72b - 1.8 = 12
Combine like terms
0.92b = 12 + 1.8
0.92b = 13.8   ⇒ divide both sides by 0.92 to get the value of b
b = 15

Substitute the value of b to eq. 3
a = 1.2b - 3
a = 1.2(15) - 3 
a = 15

to check: substitute the values of a and b to:
eq. 1
a - 1.2b = - 3 
15 - (1.2)(15) = -3 
15 - 18 = - 3 
- 3 = -3    ⇒ correct!

eq. 2 
0.2b + 0.6a = 12 
(0.2)(15) + (0.6)(15) = 12
3 + 9 = 12
12 = 12   ⇒ correct!

Answer 2

Answer:

the answer is A on edgenuity

Step-by-step explanation:

(15,15)