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3 years ago

12. If 3x + 4y = -1 and x - 2y = 3, then y=

Mathematics

1 answer:

Hatshy [7]3 years ago

6 0

y=3 and x= 5

Step-by-step explanation:

3×+×=-1 and 4y-2y=3
4×=1 and 2y=3
×=4-1 and y=3+2
x=3 and y=5

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Faith reads each night before bed. She read 623 pages last week. If she read the same number of pages every night, which equatio

Alona [7]

Answer:

x= 623/7 x =89 89 pages every night

Step-by-step explanation:

A week has 7 days

She reads 623 pages in one week(623 in 7 days)

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3 years ago

This is due tomorrow, so please help and show step by step

Softa [21]

Answer:

slope = 3/2
y-intercept = 3
x-intercept = -2

Step-by-step explanation:

The slope is the coefficient of x when the equation is of the form ...

y = (something).

Here, we can put the equation in that form by subtracting 12x and dividing by the coefficient of y:

12x -8y = -24 . . . . . given

-8y = -12x -24 . . . . .subtract 12x

y = 3/2x +3 . . . . . . . divide by -8

This is the "slope-intercept" form of the equation. Generically, it is written ...

y = mx + b . . . . . . where m is the slope and b is the y-intercept

So, the above equation answers two of your questions:

slope = 3/2

y-intercept = 3

The x-intercept is found fairly easily from the original equation by setting y=0:

12x = -24

x = -24/12 = -2 . . . . . the x-intercept

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A graph of the equation can also show you these things. The graph shows a rise of 3 units for a run of 2, so the slope is rise/run = 3/2. The line crosses the axes at x=-2 and y=3, the intercepts.

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3 years ago

Give the coordinates of a point on the line whose equation in point-slope form is.

pantera1 [17]

Answer:

(4, -2)

Step-by-step explanation:

The point-slope form of the equation for a line is ...

y -k = m(x -h)

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Comparing this to the equation you're given, you can see that the point that was used is (h, k) = (4, -2).

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3 years ago

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VladimirAG [237]

1)

LHS = cot(a/2) - tan(a/2)

= (1 - tan^2(a/2))/tan(a/2)

= (2-sec^2(a/2))/tan(a/2)

= 2cot(a/2) - cosec(a/2)sec(a/2)

= 2(1+cos(a))/sin(a) - 1/(cos(a/2)sin(a/2))

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= 2[(1+cos(a) -1)/sin(a)]

=2cot a

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2.

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3 years ago

Can you help me with this!!!!!!!!!

alexira [117]

a. The first variable is x and the second variable is y.

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