Step-by-step explanation:
<u>Statement Reason </u>
∠5 and ∠7 are vertical angles Vertical angles theorem
m∠5 = m∠7 Definition of vertical angles
m∠5 = -2(3x - 4), m∠7 = 3(x - 3) - 1 Given
-2(3x - 4) = 3(x - 3) - 1 Substitution property of equality
-6x + 8 = 3x - 9 - 1 Distributive property
3x + 6x = 8 + 10 Addition property
9x = 18 Addition property
x = 18/9 Division property
x = 2 Proved
Answer: the speed of the boat on the lake is 9 mph
Step-by-step explanation:
Let x represent the speed of the boat on the lake or in still water.
The speed of the current in a river is 6 mph. This means that if the boat goes upstream against the speed of the current, its total speed would be (x - 6)mph. If the boat goes downstream against the speed of the current, its total speed would be (x + 6)mph.
Time = distance/ speed
Every day, his route takes him 22.5 miles each way against the current and back to his dock, and he needs to make this trip in a total of 9 hours. This means that the time taken to travel upstream is
22.5/(x - 6). The time taken to travel downstream is
22.5/(x + 6)
Since the total time is 9 hours, it means that
22.5/(x - 6) = 22.5/(x + 6)
Cross multiplying, it becomes
22.5(x + 6) + 22.5(x - 6) = 9
Multiplying through by (x + 6)(x - 6), it becomes
22.5(x - 6) + 22.5(x + 6) = 9[(x + 6)(x - 6)]
22.5x - 135 + 22.5x + 135 = 9(x² - 6x + 6x - 36)
22.5x + 22.5x = 9x² - 324
9x² - 45x - 324 = 0
Dividing through by 9, it becomes
x² - 5x - 36 = 0
x² + 4x - 9x - 36 = 0
x(x + 4) - 9(x + 4) = 0
x - 9 = 0 or x + 4 = 0
x = 9 or x = - 4
Since the speed cannot be negative, then x = 9
Answer:
y=8
Step-by-step explanation:
Y=x+5
Let x =3
y = 3+5
y=8
The area of the composite polygon is:

<h2>
Explanation:</h2><h2 />
Hello! remember you have to write complete questions in order to get good and exact answers. Here you haven't provided any figure, so I'll choose the figure below in order to illustrate this problem. A composite polygon is a polygon that can be divided into two or more basic shapes. So here we have a composite polygon formed by a triangle and a rectangle. So:

So the area of the composite figure is:

<h2>
Learn more:</h2>
Dilation: brainly.com/question/10946046
#LearnWithBrainly
Answer:
x = 0
Step-by-step explanation:
both angles equal each other
I hope this helps