What are the x-intercepts of the equation $f (x) = 3 x^{2} + 10 x - 8$ $f(x)=3x^2+10x-8$ ?

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Answer 1 · 2017-10-26T05:49:36

$x = \frac{2}{3} and x = - 4$ $x = 2/3 and x =-4$ are the $x$ $x$ -intercepts

The $x$ $x$ intercepts are the points where the parabola crosses the $x$ $x$ -axis.

All along the $x$ $x$ -axis, $y = 0$ $y=0$ . This gives us the equation:

$3 x^{2} + 10 x - 8 = 0 \leftarrow$ $3x^2+10x-8=0" "larr$ factorise and solve for $x$ $x$

$(3 x - 2) (x + 4) = 0$ $(3x-2)(x+4)=0$

Set each factor equal to $0$ $0$

$3 x - 2 = 0 \to 3 x = 2 \to x = \frac{2}{3}$ $3x-2=0" "rarr 3x=2" "rarr x= 2/3$

$x + 4 = 0 \to x = - 4$ $x+4=0" "rarr x= -4$

What are the x-intercepts of the equation f(x)=3x2+10x−8f(x)=3x^2+10x-8 ?