How do you evaluate $\sqrt{b^{2} - 4 a c}$ $sqrt(b^2-4ac)$ for a=-9, b=10, c=-1?

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Answer 1 · 2017-07-19T03:39:42

See a solution process below:

To evaluate this expression substitute:

$- 9$ $color(red)(-9)$ for $a$ $color(red)(a)$

$10$ $color(blue)(10)$ for $b$ $color(blue)(b)$

$- 1$ $color(green)(-1)$ for $c$ $color(green)(c)$

$\sqrt{b^{2} - 4 a c}$ $sqrt(color(blue)(b)^2 - 4color(red)(a)color(green)(c))$ becomes:

$\sqrt{10^{2} - (4 \cdot - 9 \cdot - 1)} \Rightarrow$ $sqrt(color(blue)(10)^2 - (4 * color(red)(-9) * color(green)(-1))) =>$

$\sqrt{100 - 36} \Rightarrow$ $sqrt(100 - 36) =>$

$\sqrt{64} \Rightarrow$ $sqrt(64) =>$

$8$ $8$

How do you evaluate √b2−4acsqrt(b^2-4ac) for a=-9, b=10, c=-1?