Construct isosceles triangle ABC such that AB = AC = 10 cm and CB = 9 cm. Measure and write down the size of angle ABC.

Mathematics

1 answer:

emmainna [20.7K]3 years ago

4 0

Answer:

∠ABC = 63.26°

Step-by-step explanation:

cos ∠ABC = (9/2)/10

cos ∠ABC = 0.45

∠ABC = 63.26°

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X^2 + 32x + 256 = 1<br>please show steps

Elena L [17]

$\boxed{x_{1}=-15} \\ \\ \boxed{x_{2}=-17}$

<h2>Explanation:</h2>

In this case, we have the following equation:

$x^2+32x+256=1$

But we can write this equation as:

$x^2+32x+256=1 \\ \\ Subtract \ -1 \ from\ both \ sides: \\ \\ x^2+32x+256-1=1-1 \\ \\ x^2+32x+255=0$

So this final result is a quadratic equation written in Standard Form ( $ax^2+bx+c=0$ ). We need to find the solutions to this equations, so let's use quadratic formula:

$x=\frac{-b \pm \sqrt{b^2-4ac}}{2a} \\ \\ a=1 \\ b=32 \\ c=255 \\ \\ \\ x=\frac{-32 \pm \sqrt{(32)^2-4(1)(255)}}{2(1)} \\ \\ x=\frac{-32 \pm \sqrt{1024-1020}}{2} \\ \\ x=\frac{-32 \pm \sqrt{4}}{2} \\ \\ x=\frac{-32 \pm 2}{2} \\ \\ Finally, \ two \ solutions: \\ \\ \boxed{x_{1}=-15} \\ \\ \boxed{x_{2}=-17}$

<h2>Learn more:</h2>

Quadratic Equations: brainly.com/question/10278062

#LearnWithBrainly

3 0

3 years ago

Which expressions are equivalent to 8 (negative 10 x + 3.5 y minus 7)? Select two options.

Elza [17]

Question is Incomplete; Complete question is given below.

Which expressions are equivalent to 8 (negative 10 x + 3.5 y minus 7)? Select two options. Negative 80 x + 24.5 y minus 56 Negative 80 x + 28 y minus 56 80 x + 28 y + 56 4 (negative 20 x + 7 y minus 14) Negative 4 (negative 20 x + 7 y minus 14)

Answer:

Negative 80 x + 28 y minus 56

4 (negative 20 x + 7 y minus 14)

Step-by-step explanation:

Given:

$8(-10x+3.5y-7)$