{3d−e=7d+e=5 use the linear combination method. the solution is (3, 2). there is no solution. the solution is (2, −1). there are infinitely many solutions.

we are given system of equation as

We are given linear combination method

In linear combination method , we always try to cancel one variable by combining two equations

step-1: Add both equations

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step-2: Divide both sides by 10

step-3: Solve for e

we can plug d=1

so, solution is (d,e)=(1,-2)..........Answer

add all the numbers and check the ones place.

the answer is 486. as the ones place is more than 4, the estimation will be the next 10 ie, 490

f(x) = x^3 -2x^2 -3x

x( x^2 -2x-3)

x( x^2 +x -3x -3)

x( x(x+1) -3(x+1))

x( x-3)( x+1)

so zeroes are 0, 3,-1

its (2) option