Answer
Find out the value of x .
To proof
SAS congurence property
In this property two sides and one angle of the two triangles are equal.
in the Δ ADC and ΔBDC
(1) CD = CD (common side of both the triangle)
(2) ∠CDA = ∠ CDB = 90 °
( ∠CDA +∠ CDB = 180 ° (Linear pair)
as given in the diagram
∠CDA = 90°
∠ CDB = 180 ° - 90°
∠ CDB = 90°)
(3) AD = DB (as shown in the diagram)
Δ ADC ≅ ΔBDC
by using the SAS congurence property .
AC = BC
(Corresponding sides of the congurent triangle)
As given
the length of AC is 2x and the length of BC is 3x - 5 .
2x = 3x - 5
3x -2x =5
x = 5
The value of x is 5 .
Hence proved
Answer:
The speed of the current is 3 miles per hour
Step-by-step explanation:
The equations for rate (r), distance (d), and time (t) are ⇒ d = rt, r = d/t, = t = d/r
Let x = speed in still water
Let c = speed of the current
The main difference with these problems is rate needs to be expressed using two variables because moving upstream the current is against you and downstream it moves with you.
Distance Rate Time
Upstream x − c
Downstream x + c
The distance column with the numbers from the problem and the value for speed in still water for x.
Distance Rate Time
Upstream 4 5 − c
Downstream 16 5 + c
The column for time using the other two columns knowing that rate, distance ⇒ time = Distance Rate Time
Upstream 4 5 − c
5 − c
4
Downstream 16 5 + c
5 + c
16
“It takes as long …” from the problem means that the two times are equal to each other. So, the equation can be written as:
4/5− c = 16/5 + c ⇒ Solve by cross-multiplying ⇒ 5(4 + c) = 16 5( − c) ⇒ c = 3
The correct answer is C. Randomizing the groups and calculating the means and difference of the means.
9, 27, 45, 54, 81,
These are the multiples of 9.
9 *1
9 *3
9 *5
9 *6
9 *9
We know that 7/10 of the cookies are chocolate chip, so that means there are 3/10 of the cookies left.
We now want to find what 3/4 of 3/10 is.
We can do this by multiplying both fractions
3/4x3/10 (we just multiply across) to get 9/40.
We cannot simplify this answer, so our final answer is 9/40 of the cookies are sugar cookies.
