Answer:
3a=4.5
Explanation:
it says that "a is equal to 3 times b", which translates to a=3b
We can substitute a as 3b in 2a+4b=5
2(3b)+4b=5
multiply
6b+4b=5
add
10b=5
divide by 10
b=1/2
since it's given that a=3b, we can multiply 1/2 by 3
a=3/2
3a is 3 times a, so we can mutiply 3(3/2)=9/2=4.5
Hope this helps!