Salutations!
[tex]5a-10b = 45[/tex]
value of [tex]b = 3[/tex]
Multiply 10 and 3
[tex]10*3=30[/tex]
Now, you can solve the equation --
[tex]5a-30=45[/tex]
separate the variables aside, and the numbers aside.
[tex]5a=45 +30[/tex]
[tex]5a=75[/tex]
[tex]a=75/5[/tex]
[tex]a=15[/tex]
Hope I helped (:
Have a great day!
