So, Katherine can do 0.1 of the job per hour. (if she needs 10 hours for the job, each hour she can do the whole divided by the time, so 1/10, which is 0.1)
if in two hours she and Marina can be done, then Marina will do 1(the whole job)-2/10 (twice as much as she can do in an hour)=0.8 of the job. So if Marina does 0.8 of the job in two hours, each hour she will do half of it: 0.4 - and this is the correct answer
Answer:
(3, 4 )
Step-by-step explanation:
3x - y = 5 → (1)
x + y = 7 → (2)
adding the 2 equations term by term will eliminate y
4x + 0 = 12
4x = 12 ( divide both sides by 4 )
x = 3
substitute x = 3 into either of the 2 equations and solve for y
substituting into (2)
3 + y = 7 ( subtract 3 from both sides )
y = 4
solution is (3, 4 )
We have
f(x)=(x-7)/(x²<span>-7x-8)
resolving the quadratic equation
using a graph tool-------- > see the attached figure
x=-1 x=8
therefore
</span>(x-7)/(x²-7x-8)=(x-7)/[(x+1)*(x-8)
the answer is -1 and 8
Answer:
sec Θ = 
Step-by-step explanation:
Using the trigonometric identity
sec²Θ = tan²Θ + 1
Since 270° < Θ < 360° ← that is fourth quadrant, then
sec Θ > 0, thus
sec²Θ = (- 
)² + 1 = 
+ 1 = 
, then
sec Θ = 
=
Answer:
x = 23
y = 128
Step-by-step explanation:
Theorem:
The measure of an exterior angle of a triangle is equal to the sum of the measures of its remote interior angles.
98 = 2x + 3x - 17
115 = 5x
x = 23
Angles 3x - 17 and y form a linear pair, so they are supplementary.
3x - 17 + y = 180
3(23) - 17 + y = 180
69 - 17 + y = 180
52 + y = 180
y = 128
