Question

if x^2+mx+20=(x+5)(x+4) find the value of m​

Answer 1

Answer:

x^2 + mx + 20 = x^2 + 4x + 5x + 20

x^2 + mx + 20 = x^2 + 9x + 20

[ cancelling from both sides i.e., x^2 and 20 ]

mx = 9x

m = 9x /x

m = 9