Given
we have
Squaring both sides, we have
And finally
Note that, when we square both sides, we have to assume that
because we're assuming that this fraction equals a square root, which is positive.
So, if that fraction is positive you'll actually have roots: choose
and you'll have
Which is a valid solution. If, instead, the fraction is negative, you'll have extraneous roots: choose
and you'll have
Squaring both sides (and here's the mistake!!) you'd have
which is not a solution for the equation, if we plug it in we have
Which is clearly false
The length is 7 with a width of 5, so the area is 35
ANSWER
x = 1.2226
EXPLANATION
To solve this equation we have to apply the property of the logarithm of the base,
Thus, we can apply the natural logarithm - whose base is e, to both sides of the equation,
Now we apply the property of the logarithm of a power,
In our equation,
Then divide both sides by 4 and solve,
The solution to this equation is x = 1.2226, rounded to four decimal places.
Answer: The is B
Step-by-step explanation:
Step-by-step explanation:
a)
we have 400 people. that is 10/10 of the whole group.
7/10 of the whole group drink tea. that is
400 × 7/10 = 40 × 7 = 280
that leaves 3/10 of the whole group not drinking tea
400 × 3/10 = 40 × 3 = 120
from the 280 tea drinkers 20% drink at lay e cups of tea each day. that is
280 × 20/100 = 28 × 2 = 56
because 20 out of 100 is the meaning of 20%.
and the remaining 80% of the tea drinkers drink less then 3 cups each day.
280 × 80/100 = 28 × 8 = 224
b)
out of the 400 people 56 drink at least 3 cups of tea each day. that is
56/400 = 7/50
