Answer:
1. 8.4 2. 15
Step-by-step explanation:
1. 4x+8y= 40
wen y= 0.8
4x+8×0.8=40
4x=40-8×0.8
4x= 40- 6.4= 33.6
....x= 33.6/4 = 8.4
2. 3a+b= 54
wen b= 9
3a+ 9= 54
3a= 54- 9
3a=45
.....a = 45/3 = 15
pls rate me
a = 15
Given
3a + b = 54 ← substitute b = 9
3a + 9 = 54 ( subtract 9 from both sides )
3a = 45 ( divide both sides by 3 )
70
7x10=70
2.4 or 12/5 or 2 2/5
-1
thats all i know :(