PLEASE HURRY WITH THIS

How many triangles can be constructed with angles measuring 50º, 90º, and 40º?

NeX [460]

Answer: Infinite

Step-by-step explanation:

We know that in a triangle the sum of all the interior angles must be 180°.

The given angles 50º, 90º and 40º

The sum of the angles 50º+ 90º + 40º= 180°

Thus, a triangle is possible with the given measurement.,

Let there is another triangle with the given angles, then by AAA similarity criteria they are similar.

Similarly, all the triangles with the same measurements of the angles must be similar.

Therefore, there are infinite number of triangles can be possible with angles measuring 50º, 90º, and 40º.

6 0

3 years ago

Read 2 more answers

Factorise the following quadratic equations

vesna_86 [32]

Answer:

see explanation

Step-by-step explanation:

In 13 - 17

Consider the factors of the constant term which sum to give the coefficient of the x- term

13

x² - x - 42 = (x - 7)(x + 6)

15

x² + x - 6 = (x + 3)(x - 2)

17

x² - 27x + 50 = (x - 25)(x - 2)

19

r² - 25 ← is a difference of squares and factors in general as

a² - b² = (a - b)(a + b) , thus

r² - 25

= r² - 5² = (r - 5)(r + 5)

5 0

3 years ago

Read 2 more answers

A right triangle has legs of lengths 9 cm and 12 cm. calculate the length of the hypotenuse?

just olya [345]

Let the legs of the triangle be a and b, and the hypotenuse c.

Your first instinct might tell you to use the Pythagorean theorem to go about solving this because $c= \sqrt{a^{2}+b^{2}}$ . This works, but it is slow.

The fastest way to solve this is to recognize that the right triangle is a special triangle where the ratio of the sides are 3:4:5. This means that if the legs are 9 and 12, then the hypotenuse is 15 because 3*3 is 9, 3*4 is 12, and 3*5 is 15.

6 0

3 years ago

Read 2 more answers

Complete the square and write in standard form. Show all work.What would be the conic section:CircleEllipseHyperbolaParabola

mote1985 [20]

ANSWER

This is an ellipse. The equation is:

$\frac{(x-1)^2}{3^2}+\frac{(y+4)^2}{4^2}=1$

EXPLANATION

We have to complete the square for each variable. To do so, we have to take the first two terms and compare them with the perfect binomial squared formula,

$(a+b)^2=a^2+2ab+b^2$

For x we have to take 16x² and -32x. Since the coefficient of x is not 1, first, we have to factor out the coefficient 16,

$16x^2-32x=16(x^2-2x)$

Now, the first term of the expanded binomial would be x and the second term -2x. Thus, the binomial is,

$(x-1)^2=x^2-2x+1$

To maintain the equation, we have to subtract 1,

$16(x^2-2x+1-1)=16((x-1)^2-1)=16(x-1)^2-16$

Now, we replace (16x² - 32x) from the given equation by this equivalent expression,

$16(x-1)^2-16+9y^2+72y+16=0$

The next step is to do the same for y. We have the terms 9y² + 72y. Again, since the coefficient of y² is not 1, we factor out the coefficient 9,

$9y^2+72y=9(y^2+8y)$

Following the same reasoning as before, we have that the perfect binomial squared is,

$(y+4)^2=y^2+8y+16$

Remember to subtract the independent term to maintain the equation,

$9(y^2+8y)=9(y^2+8y+16-16)=9((y+4)^2-16)=9(y+4)^2-144$

And now, as we did for x, replace the two terms (9y² + 72y) with this equivalent expression in the equation,

$16(x-1)^2-16+9(y+4)^2-144+16=0$

Add like terms,

$\begin{gathered} 16(x-1)^2+9(y+4)^2+(-16-144+16)=0 \\ 16(x-1)^2+9(y+4)^2-144=0 \end{gathered}$

Add 144 to both sides,

$\begin{gathered} 16(x-1)^2+9(y+4)^2-144+144=0+144 \\ 16(x-1)^2+9(y+4)^2=144 \end{gathered}$

As we can see, this is the equation of an ellipse. Its standard form is,

$\frac{(x-h)^2}{a^2}+\frac{(y-k)^2}{b^2}=1$

So the next step is to divide both sides by 144 and also write the coefficients as fractions in the denominator,

$\begin{gathered} \frac{16(x-1)^2}{144}+\frac{9(y+4)^2}{144}=\frac{144}{144} \\ \\ \frac{(x-1)^2}{\frac{144}{16}}+\frac{(y+4)^2}{\frac{144}{9}}=1 \end{gathered}$

Finally, we have to write the denominators as perfect squares, so we identify the values of a and b. 144 is 12², 16 is 4² and 9 is 3²,

$\frac{(x-1)^2}{(\frac{12}{4})^2}+\frac{(y+4)^2}{(\frac{12}{3})^2}=1$

Note that we can simplify a and b,

$\frac{12}{4}=3\text{ and }\frac{12}{3}=4$

Hence, the equation of the ellipse is,

$\frac{(x-1)^2}{3^2}+\frac{(y+4)^2}{4^2}=1$

3 0

1 year ago

A cell phone that regular costs $780 is on sale for 15% off. What is the total cost of the phone if you have to pay 5.5% sales t

Alex_Xolod [135]

Answer:

$700

Step-by-step explanation:

Step one:

Given data

Regular cost of cell phone= $780

discount = 15%

tax = 5.5%

Step two

Let us compute the discounted amount

= 15/100*780

=0.15*780

=$117

hence the selling price is

=780-117

=$663

Also, the tax-deductible is

=5.5/100*663

=0.055*663

=$36.465

The total cost of the phone will be

=663+36.465

=699.465

=$700 to the nearest cent

8 0

3 years ago