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2 years ago

Solve the system of equations. -5x+2y=9. y=7x

Mathematics

1 answer:

il63 [147K]2 years ago

7 0

$- 5x + 2y = 9 \\ y = 7x \\ \\ - 5x + 2 \times 7x = 9 \\ - 5x + 14x = 9 \\ 9x = 9 \\ x = 1 \\ \\ y = 7 \times 1 = 7 \\$

Answer: (1; 7)

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Math practice <br> Will give brainest if correct

svetoff [14.1K]

Answer:

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Step-by-step explanation:

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2 years ago

What is an<br> equation of the line that passes through the points (-3,8) and (4,1)?

GuDViN [60]

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Step-by-step explanation:

(-3,8) ( 4,1)

8-1= 7

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2 years ago

Is 5(3x +4) equivalent to 15x + 20 ?

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Answer:

yes

Step-by-step explanation:

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8 0

2 years ago

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En un triángulo rectángulo A es un ángulo agudo y Sen A = 4/5 ¿Cuál será el valor de Tan A?

Nonamiya [84]

Answer:

$\displaystyle \tan A=\frac{4}{3}$

Step-by-step explanation:

<u>Funciones Trigonométricas</u>

La identidad principal en trigonometría es:

$sen^2A+cos^2A=1$

Si sabemos que A es un ángulo agudo (que mide menos de 90°), su seno y coseno son positivos.

Dado que Sen A = 4/5, calculamos el coseno:

$cos^2A=1-sen^2A$

Sustituyendo:

$\displaystyle cos^2A=1-\left(\frac{4}{5}\right)^2$

$\displaystyle cos^2A=1-\frac{16}{25}$

$\displaystyle cos^2A=\frac{25-16}{25}$

$\displaystyle cos^2A=\frac{9}{25}$

Tomando raíz cuadrada:

$\displaystyle cos\ A=\sqrt{\frac{9}{25}}=\frac{3}{5}$

La tangente se define como:

$\displaystyle \tan A=\frac{sen\ A}{cos\ A}$

Substituyendo:

$\displaystyle \tan A=\frac{\frac{4}{5}}{\frac{3}{5}}$

$\displaystyle \tan A=\frac{4}{3}$

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2 years ago

) Write an expression that is equivalent to 3(7 + x).

Mamont248 [21]

same question how many times...?

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2 years ago

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