Pls help me not fail
1 answer:
Answer:
D
Step-by-step explanation:
Using the Cosine rule to find AC
AC² = BC² + AB² - (2 × BC × AB × cosB )
= 18² + 12² - ( 2 × 18 × 12 × cos75° )
= 324 + 144 - 432cos75°
= 468 - 111.8
= 356.2 ( take the square root of both sides )
AC = ≈ 18.9
-----------------------------------------
Using the Sine rule to find ∠ A
=
( cross- multiply )
18.9 sinA = 18 sin75° ( divide both sides by 18.9 )
sinA = , then
∠ A = (
) ≈ 66.9°
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Answer:
, or x-2y=14
Step-by-step explanation:
Hi there!
We want to find the equation of the line that passes through the point (2, -6) and is parallel to the line x-2y=8
First, we need to find the slope of x-2y=8, since parallel lines have the same slopes
We can convert the equation from standard form (ax+by=c) to slope-intercept form (y=mx+b, where m is the slope and b is the y intercept), in order to help us find the slope of the line
Start by subtracting x from both sides
-2y=-x+8
Divide both sides by -2
y=-4
The slope of the line x-2y=8 is 1/2
It's also the slope of the line parallel to it.
Since we know the slope of the line, we can plug it into the equation for slope intercept form:
Now we need to find b.
As the equation of the line passes through (2, -6), we can use it to help solve for b
Substitute -6 as y and 2 as x:
Multiply
-6=1+b
Subtract 1 from both sides
-7=b
Substitute -7 as b into the equation:
The equation can be left as that, or you can convert it into standard form if you wish.
In that case, you will need to move 1/2x to the other side:
A rule about the coefficients a, b, and c in standard form is that a (coefficient in front of x) CANNOT be negative, and every coefficient must be an integer (a whole number, not a fraction or decimal).
So multiply both sides by -2 in order to clear the fraction, as well as change the sign of a
x-2y=14
Hope this helps!