Grade 10 Math help?

Question

Does anyone know how you would solve the equations:

3x ^ 2 - 17x=0
through the quadratic function equation thing:
y= -b +/- (square root of:) b^2 - 4a/2a

Answer 1

3x² - 17x = 0

Quadratic formula:
[ -b ± √(b² -4ac)] / 2a

For your equation, a = 3, b = -17, c = 0

[17 ± √( (-17)² - (4)(3)(0) ) ] / (2)(3)

= [ 17 ± √(-17)² ] / 6

= [17 ± 17 ] / 6

= 0 or 34/6

= 0 or 17/3

Answer 2

Are you required to use the quadratic formula? It would be a lot easier to factor. 3x^2 - 17x = x(3x - 17), so x = 0 or 3x - 17 = 0 ==> x = 17/3.

In any event, the form of the equation used for the quadratic formula is ax^2 + bx + c = 0. The equation 3x^2 - 17x = 0 may be throwing you because it looks like there is no c. That's because c = 0. Also, a = 3 and b = -17.

You've written the quadratic formula incorrectly; it should be x = (-b +/- sqrt(b^2 - 4ac)) / (2a). Now plug in the values for a, b, and c. x = (17 +/- sqrt(289 - 4*3*0)) / (2*3) = (17 +/- sqrt(289)) / 6 = (17 +/- 17) / 6 = (0 or 34) / 6 = 0 or 17/3, which checks out with the above.

Answer 3

a = 3 b = -17 c = 0

x = 17+/-(square root of:) [ ( -17)^2 - 4 x 3 x 0 ] / 6

= 17 +/- (square root of:) ( 289 ) / 6
= [17 +/- 17 ] / 6

x = [ 17 - 17 ] /6 and x = [ 17 + 17 ] / 6

= 0 / 6 = 34 / 6
= 0 = 17 / 3

x = 0 and 17 / 3

Answer 4

Quadratic Formula
x=(-b +/- SQUAREROOT(b^2 - 4*a*c) )/2*a
(not sure about brackets but anyways..)

a=3
b=-17
c=0 (not present)
since the equation is in the form ax^2+bx+c=0 standard form and unfactored...you can easily identify a b and c

the equation has 2 roots 1 at
5.666666666666667
and 1 at 0
according to http://www.math.com/students/calculators/source/quadratic.htm
(which I believe means 2 equal roots and the parabola touches one point 5.66 on the x axis)

P.S. Solve yourself and confirm, don't use this calculator to do your homework, or you will be crippled in a test situation.

Answer 5

well just by looking at it i can tell 0 is one answer. The other answer would be 5 2/3 I took an x out and had x(3x-17) and then got each to equal 0

Answer 6

x = [ 17 ± √(17² - 0) ] / 6
x = [ 17 ± 17 ] / 6
x = 17/3 , x = 0

Answer 7

the thing is that c=0.
then you have
a=3
b=-17
c=0

sol. x1= 0; x2=17/3