Question

If m=qx²-4xy+5y²and n=-3x²+2xy-y²find m+2n​

Answer 1

Answer:

m = 9x2 – 4xy + 5y2

n = 3x2 + 2xy – y2

(i) 2m – n = 2(9x2 – 4xy + 5y2) – (-3x2 + 2xy – y2)

= 18x2 – 8xy + 10y2 + 3x2 – 2xy + y2

= 18x2 + 3x2 – 8xy – 2xy + 10y2 + y2

= 21x2 – 10xy + 11y2

(ii) m + 2n = (9x2 – 4xy + 5y2) + 2(-3x2 + 2xy – y2)

= 9x2 – 4xy + 5y2 – 6x2 + 4xy – 2y2

9x2 – 6x2 – 4xy + 4xy + 5y2 – 2y2

= 3x2 + 3y2

(iii) m = 9x2 – 4xy  +5y2

n = -3x2 + 2xy – y2

Now, m – 3n = 9x2 – 4xy + 5y2 – 3(-3x2 + 2xy – y2)

= 9x2 – 4xy + 5y2 + 9x2 – 6xy + 3y2

= 18x2 – 10xy + 8y2

Step-by-step explanation: