Question

10-10:{1+3×[(39-60: a x2) +21]: 103=9​

Answer 1

10-10/[1+3·[39-60/a·2]+21]/10]=9

⇒10/[1+3·[39-60/a·2]+21]/10]=10-9

⇒10/[1+3·[39-60/a·2]+21]/10]=1

⇒1+3·[39-60/a·2]+21]/10]=10/1

⇒1+3·[39-60/a·2]+21]/10]=10

⇒3·[39-60/a·2]+21]/10]=10-1

⇒3·[39-60/a·2]+21]/10]=9

⇒[39-60/a·2]+21]/10]=9/3

⇒[39-60/a·2]+21]/10]=3

⇒[39-60/a·2]+21]=10·3

⇒[39-60/a·2]+21]=30

⇒[39-60/a·2]=30-21

⇒[39-60/a·2]=9

⇒39-60/a·2=9

⇒60/a·2=39-9

⇒60/a·2=30

⇒60/a=30/2

⇒60/a=15

⇒a=60/15

⇒a=4;