Answer:
1st number: 22
2nd number: 16
3rd number: 64
Step-by-step explanation:
x + y + z = 102
x = 6 + y
z = 4y
plug that in!
(6 + y) + y + (4y) = 102
get rid of the parenthesis (I added them so you could see what I was replacing) and add like terms.
6 + 6y = 102
move 6 to the other side.
6y = 96
y = 16
now that you know one number, you can solve the equations for the rest!
x = 6 + (16)
z = 4(16)
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x = 22
y = 16
z = 64
Answer:
x = 9
Step-by-step explanation:
7x = 63
Divide each side by 7 to isolate x
7x/7 = 63/7
x = 9
1. If the line that we are searching for is perpendicular to the line y = -4x, this means that the gradient of our line and the gradient of the perpendicular line will multiply to give -1. Thus if we call the gradient of our line m, then:
m*(-4) = -1
-4m = -1
m = 1/4
2. Since we know that m = 1/4 and we have a point (2,6) on our line, we can use the formula y - y1 = m(x - x1) to find the equation of our line, where (x1, y1) is the coordinates of a point on the line. Thus:
y - y1 = m(x - x1)
y - 6 = (1/4)(x - 2)
y - 6 = (1/4)x - 2/4 (Expand (1/4)(x - 2))
y = (1/4)x - 1/2 + 6 (Simplify 2/4 and add 6 to each side)
y = (1/4)x + 11/2 (Evaluate -1/2 + 6)
Slope-intercept form is given by y = mx + c. As our equation is already in this form, there is nothing more to do. Thus, the answer is y = (1/4)x + 11/2
Just remember it's along the corridor and up the stairs so horizontal comes first
Answer:
- sin(4a) = -24/25
- cos(4a) = 7/25
Step-by-step explanation:
Your calculator can tell you these values:
sin(4a) = sin(4·arctan(3)) = -0.96 = -24/25
cos(4a) = cos(4·arctan(3)) = 0.28 = 7/25
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Some useful trig identities are ...
sin(2a) = 2tan(a)/(1 +tan(a)^2)
cos(2a) = (1 -tan(a)^2)/(1 +tan(a)^2)
Filling in the given value for tan(a), we find ...
sin(2a) = 2(3)/(1+3^2) = 6/10 = 3/5
cos(2a) = (1 -3^2)/(1 +3^2) = -8/10 = -4/5
Now, double-angle formulas are useful:
sin(4a) = 2sin(2a)cos(2a) = 2(3/5)(-4/5) = -24/25
cos(4a) = 1 -2sin(2a)^2 = 1 -2(3/5)^2 = 7/25
The desired trig function values are sin(4a) = -24/25; cos(4a) = 7/25.
