Solve for x in 2nd equation
times -1 both sides
x-5=6y
add 5
x=6y+5
sub
5(6y+5)+4y=-26
30y+25+4y=-26
34y+25=-26
minus 25 both sides
34y=-51
divide both sides by 34
y=-3/2
sub back
x=6y+5
x=6(-3/2)+5
x=-18/2+5
x=-9+5
x=-4
(-4,-3/2) is solution
Answer:
Step-by-step explanation:
1) A perfect square is a whole number which is a product of a smaller whole number and itself. Examples of perfect squares are
4(2 × 2)
9(3 × 3)
16(4 × 4)
25(5 × 5)
36(6 × 6)
2) Square root of 4x² is 2x(product of square root of 4 and square root of x²)
3) square of 25 is 5
4) 4x² + 20x + 25
The general formula for solving quadratic equations is expressed as
x = [- b ± √(b² - 4ac)]/2a
From the equation given,
a = 4
b = 20
c = 25
Therefore,
x = [- 20 ± √(20² - 4 × 4 × 25)]/2 × 4
x = [- 20 ± √(400 - 400)]/8
x = [- 20 ± 0]/8
x = - 20/8
x = - 2.5
Idk your best bet is to look it up online thats what i do often
Answer: There are two solutions and they are
theta = 135
theta = 225
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Explanation:
Recall that x = cos(theta). Since the given cosine value is negative, this indicates x < 0. Theta is somewhere to the left of the y axis, placing it in quadrant 2 or quadrant 3.
It turns out there are two solutions, with one solution per quadrant mentioned above. Use the unit circle to find that the two solutions are:
theta = 135
theta = 225
You're looking for points on the unit circle that have x coordinate equal to x = -sqrt(2)/2. Those two points correspond to the angles of 135 and 225, which are in quadrants 2 and 3 respectively.
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I recommend using your calculator to note that
-sqrt(2)/2 = -0.70710678
cos(135) = -0.70710678
cos(225) = -0.70710678
The decimal values are approximate. Make sure your calculator is in degree mode. Because those three results are the same decimal approximation, this indicates that cos(135) = cos(225) = -sqrt(2)/2.
