12 Bc u make a common denimater
Well to divide 2 fraction you first have to find a least common number between the 2 bottom numbers in the fractions, we know automaticall that 15 fits in both the 3 and the 5. now u have to find out what to multiply by each number to get 15, for example what number do you multiply by 3 to get 15?? well it will be 5, so go ahead and multiply it by the fraction (note that what you do in the bottom you have to do in the top) this will give you 10/15, because I multiplied the top and bottom number by 5... lets try the other one what number do you multiply by 5 to get 15?? well it will be 3 so go ahead and multiply that to get 12/15.. now add the top numbers (note that the bottoms always stay the same, you never add or subtract them) when you do you will get 22/15, now you have to see if you can simplify it any further in this case you can't so your final answer is 22/15
Hope this helps
can take a picture of the problem and upload it
Step-by-step explanation:
=>a+6a=90-12
=>7a=78
=>a=11,14
