Hi there!
One and one tenth looks hard but that would be because it's in word form.
In standard, or decimal form, this would be 1.1.
The first 1 represents the whole number and the second 1 represents the tenths.
Hope this helps! Let me know if you need anymore help! :)
3.5 + 2 = 2x - 10
5.5 = 2x -10
+10 +10
—————————
15.5 = 2x
—— ——
2 2
7.75 = x
7.75 is the answer
Answer:
a. 
b. x = 4 (see steps below)
Step-by-step explanation:
Since the two polygons are similar, the sides are proportional to each other. Using a proportion, you can solve for 'x' using cross-multiplication and division:
Cross-multiply: 15(x + 3) = 21(x + 1)
Distribute: 15x + 45 = 21x + 21
Subtract '15x' from both sides: 15x + 45 - 15x = 21x + 21 - 15x or 45 = 6x + 21
Subtract '21' from both sides: 45 - 21 = 6x + 21 - 21 or 24 = 6x
Divide by 6 on both sides: 24/6 = 6x/6
Solve for x: x = 4
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
_____
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.
Properties we are going to use :
1. (a^m)^n = a^mn
2. a^m : a^n = a^(m-n)
((a^-2)^-1)^-1 = (a^(-2 x -1))^-1 = (a^2)^-1 = a^-2
(a : a^-1)^2 = (a^1 - (-1))^2 = (a^2)^2 = a^4
Therefore, the expression is simplified down to a^-2 : a^4
a^-2 : a^4 = a^(-2 - 4) = a^-6.
