Question

Solve the system. x + y = 8 2x2 – y = –5 Add the equations, then choose the result. 3x2 = –13 3x2 = 3 2x2 + x = 3 2x2 = –13

Answer 1

2x^2 - y = -5
     x + y = 8
----------------add
2x^2 + x = 3 <==

** 2x^2 and x cannot be added because they are not like terms

Answer 2

Answer:

Option 3rd is correct

$2x^2+x=3$

Step-by-step explanation:

Solve the system of equation:

$x+y = 8$             ....[1]

$2x^2-y = -5$            ....[2]

we can write equation [2] as :

$y= 2x^2+5$

Substitute the value of y in [1] we have;

$x+2x^2+5 = 8$

Subtract 5 from both sides we have;

$x+2x^2=3$

or

$2x^2+x=3$

Therefore, the result we get, $2x^2+x=3$