Answer:
(a) 1/2
(b) 9/10
Step-by-step explanation:
Probability is given by number of possible outcomes ÷ number of total outcomes
(a) Number of possible outcomes = 5 questions, number of total outcomes = 10 questions
Probability (I answer all 5 problems correctly) = 5/10 = 1/2
(b) Probability (I answer at least 4 of the problems correctly) means I either answer 4 of the problems or all 5 problems correctly = 4/10 + 5/10 = 9/10
Cancel out the denominators.
(x+5)² + 18 = -30
(x+5)² = -30 - 18
(x+5)² = -48
The equation is impossible, we have a negative number.
There isn't a number that squared gives a negative number (the square is always positive).
√(x+5)² = +/- √-48
x+5 = +/- √-48
IMPOSSIBLE
You can write the result in imaginary numbers
x+5=+/- 4i√3
The first one is 0,5 the second one is 1,3 last one is 2,1
1.) 9 cm
2.) 5 cm
3.) 10 in
4.) 4 in
The area of a circle is A = πr^2. We let A1 And A2 the areas of the circles and r1 and r2 the radius of each, respectivley.
A1 + A2 = 80π
Substitute the formula for the area,
π(r1)^2 + π (r2)^2 = 80π
From the statement, we know that r2=2(r1).
<span>π(r1)^2 + π (2 x r1)^2 = 80π
</span>We can cancel π, we will have
5 x (r1)^2 = 80
Thus,
r1 = 4 and r2 = 8
