question_answer

(a) From the sum of 3xy + 11 and  y  11, subtract 3x   y 11.

(b) From the sum of 4 + 3x and \[5-4x+2{{x}^{2}},\] subtract the sum of \[3{{x}^{2}}-5x\] and\[-{{x}^{2}}4-2x+5\].

 

Answer:

(a) The sum of 3x - y + 11 and - y -11 is given by (3x ? y + 11) + (-y - 11) = 3x - y+ 11-y - 11

= 3x - 2y

Now, we have to subtract 3x - y -11 from 3x - 2y. Required expression = (3x - 2y) - (3x -y-11)

= 3x - 2y - 3x + y + 11

=-y + 11

(b) The sum of 4 + 3x and \[5-4x+2{{x}^{2}}\] is given by

\[\left( 4+3x \right)+\left( 5-4x+2{{x}^{2}} \right)=4+3x+5-4x+2{{x}^{2}}\]

\[=9-x+2{{x}^{2}}\]

The sum of \[3{{x}^{2}}-5x\] and \[-\text{ }{{x}^{2}}+2x-t-5\] is given by

\[\left( 3{{x}^{2}}-5x \right)+\left( -{{x}^{2}}+2x+5 \right)\]

\[=\text{ }3{{x}^{2}}-5x-x2+2x+5\]

\[=\text{ }2{{x}^{2}}-3x+5\]

Now, we have to subtract 2x2 - 3x + 5 from

\[9-x+2{{x}^{2}}\]

\[\therefore \]Required expression\[=\left( 9-x+2{{x}^{2}} \right)-\]

\[\left( 2{{x}^{2}}-3x+5 \right)\]

\[=9-x+2{{x}^{2}}-2{{x}^{2}}+3x-5\]

= 2x + 4.