Answer:
41/5
Step-by-step explanation:
First we change the 8 and 1/5% to 8.2%
Write the fraction down as a number over one = 8.2/1
Multiply both top and bottom by 10 for every number after the decimal point:
As we have 1 numbers after the decimal point, we multiply both numerator and denominator by 10. So,
8.2/1 = (8.2 × 10)
(1 × 10) = 82/10
Reduce the above fraction by dividing both numerator and denominator by the GCD (Greatest Common Divisor) between them. In this case, GCD (82,10) = 2. So, (82÷2)/(10÷2) = 41/5 when reduced to the simplest form.
As the numerator is greater than the denominator, we have an IMPROPER fraction, so we can also express it as a MIXED NUMBER, thus 82/10 is also equal to 81/5 when expressed as a mixed number.
The correct question is
Use the given information to find the exact value of the expression. sin α = 21/29, α lies in quadrant II, and cos β = 15/17, β lies in quadrant I Find sin (α - β).
we know that
sin(α − β<span>) = </span>sin α cos β − cos α sin β
α lies in quadrant II
so
cos α is negative
sin α is positive
β lies in quadrant I
so
cos β is positive
sin β is positive
step 1
find sin β
cos β=15/17
sin² β+cos² β=1-----------> sin² β=1-cos² β----> sin² β=1-(15/17)²
sin² β=1-225/289-----> 64/289
sin β=8/17
step 2
find cos α
sin α = 21/29
cos² α + sin² α=1----> cos² α=1-sin² α---> cos² α=1-(21/29)²---> 1-441/841
cos² α=400/841------> cos α=-20/29 (remember cos α is negative)
step 3
find sin(α − β)
sin α = 21/29 cos α=-20/29
sin β=8/17 cos β=15/17
sin(α − β) = [21/29]*[15/17] − [-20/29*]*[8/17]
sin(α − β) = [315/493] − [-160/493]
sin(α − β) = 475/493
the answer is
sin(α − β) = 475/493
Answer:
b) 4x
Step-by-step explanation:

This is a basic algebraic word problem. Make x equal the miles you traveled. multiply that by 2 and add the 3 initial dollars, then add the one dollar tip, finally make all this equal to 20. So your equation should look like this:
2x + 3 + 1 = 20
add the 3 and 1:
2x + 4 =20
move the 4 to the right side:
2x = 16
devide both sides by 2:
x = 8
So you traveled 8 miles.