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3 years ago

3x+y=15 5x-4y=8 resolucion de sistema por el metodo de sustitucion

Mathematics

1 answer:

Brrunno [24]3 years ago

8 0

Answer:

x=4

y=3

Step-by-step explanation:

we have the following equations

3x+y=15 equation 1

5x-4y=8 equation 2

using equation 1 we have:

y=15-3x equation 3

using equation 3 in equation 2 we have:

5x-4(15-3x)=8

5x-4*15+4*3x =8

5x-60+12x = 8

17x=68

x=68/17

so we have x=4

finally in equation 3:

y = 15-3(4)

y = 15-12

y = 3

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Answer:

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Explanation:

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Step-by-step explanation:

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3 years ago

Given: ABCD is a trapezoid, AC ⊥ CD AB = CD, AC=the square root of 75 , AB = 5 Find: AABCD

Ugo [173]

In this attached picture according to the conditions of the problem we have an isosceles trapezoid and since we know that legs are equal (AD=BC=5 cm), we have to calculate bases and height in order to find the area. Working with the triangle BCD, we apply Pythagoras theorem and find that CD = $\sqrt{75+25}$ = 10 cm. Since BDC is a right triangle, applying theorem for the area of triangles, we find that $\frac{1}{2} * BF = \frac{1}{2} * 5 * \sqrt{75}$ and BF= $0.5\sqrt{75}$ . Since ABCD is an isosceles trapezoid, triangles ADE and BFC are congruent with Angle Side Angle theorem. Then, DE=FC and with the help of Pythagoras theorem, DE=FC=2.5 cm. Then, AB=EF=5 cm and the area of the trapezoid is $A= BF * \frac{AB+CD}{2} = 0.5 \sqrt{75} * \frac{5+10}{2} = 18.75 \sqrt{3} cm^{2}$

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Step-by-step explanation:

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Read 2 more answers

Sketch these cartesin products on the x-y plane R^2<br><br> 14. 11,21x1,1.5,2

ale4655 [162]

Answer:

$\left\{11, 21\right\} \times \left\{1, 1.5, 2\right\} = \left\{ (11, 1), (11, 1.5), (11, 2), (21, 1), (21, 1.5), (21, 2)\right\}$

Step-by-step explanation:

The Cartesian product between two discrete sets, is given by all possible ordered pairs originated with the combinations of the elements of the two sets, thus the requested Cartesian product is:

$\left\{11, 21\right\} \times \left\{1, 1.5, 2\right\} = \left\{ (11, 1), (11, 1.5), (11, 2), (21, 1), (21, 1.5), (21, 2)\right\}$

$A = (11, 1)\\B = (11, 1.5)\\C = (11, 2)\\D = (21, 1)\\E = (21, 1.5)\\F = (21, 2)\\$

You can see the attached file

Download pdf

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3 years ago