Steps:
1. Multiply the first line by 3 and the second by 2
3(3x + 2y= 4)
2(8x -3y=-6)
2. New lines are
9x + 6y= 12
16x + -6y=-12
3. Now add/subtract them
25x + 0= 0
25x=0
4. Divide by 25
X=0

5. To find y, substitute the 0 in the x in one of the equations
9x + 6y= 12
9(0) + 6y= 12
6y= 12
6. Divide by 6, your Y=2
7. X=0, Y=2

7 0

2 years ago

(a) Use the fundamental theorem of algebra to determine the number of roots for 2x^2 + 4x + 7

zysi [14]

Answer:

Step-by-step explanation:

A 2nd order polynomial such as this one will have 2 roots; a 3rd order polynomial 3 roots, and so on.

The quadratic formula is one of the faster ways (in this situation, at least) in which to find the roots. From 2x^2 + 4x + 7 we get a = 2, b = 4 and c = 7.

Then the discriminant is b^2 - 4ac, or, here, 4^2 - 4(2)(7), or -40. Because the discriminant is negative, we know that the roots will be complex and unequal.

Using the quadratic formula:

-4 ±√[-40] -4 ± 2i√10

x = ------------------ = ------------------

4 4

-2 ± i√10

Thus, the roots are x = ------------------

4 0

2 years ago