We first need to multiply:
5(2)(3)
5(2)=10 and 10(3)=30
After simplifying, the equation is:
a+30=9
Solving for a, subtract 30 from both sides to cancel it out and combine it with the 9 constant:
a=9-30
a=-21
We can substitute a=-21 back into the equation to check it satisfies it:
(-21)+30=9
So, the solution a=-21 is correct.