Answer:
x^2 - 25 ✔
Step-by-step explanation:
(x+5)(x-5)
x(x-5) +5(x-5)
x^2 - 5x + 5x - 25
x^2 - 25
Answer:
The value of cos Ф is ± 
Step-by-step explanation:
There are important rules for sin Ф and cos Ф
∵ sin Ф = 
∴ sin²Ф = 
∴ sin²Ф = 
→ By using the third rule above
∵ cos²Ф = 1 - sin²Ф
∴ cos²Ф = 1 -
∴ cos²Ф = 
→ Take square root for both sides
∴ cos Ф = ±
∴ The value of cos Ф is ±
Answer: 17 cm
Step-by-step explanation:
84 - 25(2) = 2x
84 - 50 = 2x
34 = 2x
x = 17
17 cm
<h3>
Answer: angle T = angle W</h3>
Explanation:
We are given the sides are congruent due to the tickmarks. Specifically
TU = WV (single tickmarks)
TV = WX (double tickmarks)
So we just need the "A" of "SAS". The A is between the two S letters, so the angle is between the two sides. For triangle TUV, the angle T is between the two sides with the tickmarks. Similarly, angle W is between the tickmarked sides of triangle WVX.
If we know that angle T = angle W, then we have enough information to use SAS.
Answer:
5 and 25
Step-by-step explanation:
let the son's age be x then the father's age is x + 20
In 5 years
son = x + 5 and father = x + 20 + 5 = x + 25
Then
x + 25 = 3(x + 5) ← father is three times as old as son
x + 25 = 3x + 15 ( subtract x from both sides )
25 = 2x + 15 ( subtract 15 from both sides )
10 = 2x ( divide both sides by 2 )
5 = x and x + 20 = 5 + 20 = 25
si=on is 5 and father is 25
