7x(15+4) = (7x ) + (7+4)

Add the numbers inside the parentheses
7x(15+4)=(7x)+(7+4)
and you get
7x*19= 7x+11

Calculate the product
133x=7x+11

Move variable to the left hand side & change its sign
133x-7x=11

Collect like terms
126x=11

Divide both sides by 126 & you get
x=11/126

x= 11/126

Hope this helps ʕ•ᴥ•ʔ

x=13

Step-by-step explanation:

so,x-10=3

or,x=3+10

or,x=13

therefore, x=13