X + y = 1
add - y both sides
x + y + - y = 1 + - y
x = - y + 1
Answer: x = - y + 1
Graph: y = - x + 1
x + 7y = - 4
add - 7 both sides
x + 7y + - 7y = - 4 + -7y
x = - 7y - 4
Answer: x = - 7y - 4
Graph: y = 0.142857x - 0.571429
2x - 6y = 4
add 6y to both sides
2x - 6y + 6y = 4 + 6y
2x = 6y + 4
divide both sides by 2
2x/2 = 6y + 4/2
x = 3y + 2
Answer: x = 3y + 2
Graph: y = 0.333333x - 0.666667
5x + 15y = - 10
add - 15 to both sides
5x + 15y + - 15y = - 10 + - 15y
5x = - 15y - 10
divide both sides by 5
5x/5 = - 15y - 10/5
x = - 3y - 2
Answer: x = - 3y - 2
Graph: y = - 0.333333x - 0.666667
2x + 6y = 10
add - 6y to both sides
2x + 6y + - 6y = 10 + - 6y
2x = - 6y + 10
divide both sides by 2
2x/2 = - 6y + 10/2
x = - 3y + 5
Answer: x = -3y + 5
Graph: y = - 0.333333x + 1.666667
Hope that helps!!!
Answer:
•cos(s+t) = cos(s)cos(t) - sin(s)sin(t) = (-⅖).(-⅗) - (√21 /5).(⅘) = +6/25 - 4√21 /25 = (6-4√21)/25
•cos(s-t) = cos(s)cos(t) + sin(s)sin(t) = (-⅖).(-⅗) + (√21 /5).(⅘) = +6/25 + 4√21 /25 = (6+4√21)/25
cos(t) = ±√(1 - sin²(t)) → -√(1 - sin²(t)) = -√(1 - (⅘)²) = -⅗
sin(s) = ±√(1 - cos²(s)) → +√(1- cos²(s)) = +√(1 - (-⅖)²) = √21 /5
Answer:
x = -1, y = 1
Step-by-step explanation:
6 + 4x - 2y = 0 (1)
-3 - 7y = 10x (2)
From (1)
6 + 4x - 2y = 0 (1)
4x - 2y = -6 (3)
From (2)
-3 - 7y = 10x (2)
10x + 7y = -3 (4)
4x - 2y = -6 (3)
10x + 7y = -3 (4)
Using elimination method
Multiply (3) by 10 and (4) by 4 to eliminate x
40x - 20y = -60
40x + 28y = -12
28y - (-20y) = -12 - (-60)
28y + 20y = -12 + 60
48y = 48
y = 48/48
y = 1
Substitute y = 1 into (3)
4x - 2y = -6 (3)
4x - 2(1) = -6
4x - 2 = -6
4x = -6 + 2
4x = -4
x = -4/4
x = -1
x = -1, y = 1
The value of x in the equation is -1
Answer:
500
Step-by-step explanation:
It's a box with a square base, so let's say the width and length are x and the height is y.
The surface area of the box without the top is:
A = x² + 4xy
300 = x² + 4xy
The volume of the box is:
V = x²y
Solve for y in the first equation and substitute into the second:
y = (300 − x²) / 4x
V = x² (300 − x²) / 4x
V = x (300 − x²) / 4
V = 75x − ¼ x³
To optimize V, find dV/dx and set to 0:
dV/dx = 75 − ¾ x²
0 = 75 − ¾ x²
x = 10
So the volume of the box is:
V = 75x − ¼ x³
V = 500
The maximum volume is 500 cm³.
Think of imaginary numbers on a complex plane as coordinates - take the real part, that's the x coordinate, the imaginary part that's the y coordinate.
Therefore, for the first blank, -1+3i lies in the shaded area, because its coordinates are (-1,3).
And following on from that for the second one, -4i does not lie in the shaded area, since its coordinates are (0,-4).
Tl;dr is taking a complex number a+bi and placing it on a complex plane, it will have coordinates (a,b)
