X+5y=15
4x+5y=0
solve for x and y

Subtract

5y from both sides of the equation.

x=15−5y

Move all terms that don't contain

y to the right side and solve.

y=−4x5

the correct answer is the second option

7! = 7×6×5×4×3×2

3! = 3× 2

as 7! is multiple of 3! because 7! contains 3! that is 3× 2 as factor

so 7! /(3! ) = 7× 6× 5× 4

= 42 × 20

= 840

its b) 840✌✌✌

dhruv⭐