Answer:
31.7 cm²
Step-by-step explanation:
The area (A) of the triangle is calculated as
A =
absinC
where a, b are the 2 sides given and C the angle between them
∠ C = 180° - (72 + 59)° = 180° - 131° = 49° , thus
A = 0.5 × 12 × 7 × sin49° ≈ 31.7 cm² ( to 1 dec. place )
Answer:
B
Step-by-step explanation:
given
- 4x²(3x - 7)
multiply each term in the parenthesis by - 4x²
= (-4x² × 3x) + ( - 4x² × - 7)
= - 12x³ + 28x² → B
Answer:
The value of n is 21.
Step-by-step explanation:
We are given that three of the exterior angle of the n-sided polygon are 50° each two of its interior angle are 127° and 135° and the remaining interior angle are 173 each.
As we know that the sum of all exterior angles of the polygon is 360°. Also, the number of remaining interior angles will be (n - 5).
And, the exterior angle = 180° - the interior angle.
So, according to the question;

150 + 53 + 45 + 7(n - 5) = 360
248 + 7n - 35 = 360
213 + 7n = 360
7n = 360 - 213
7n = 147
n = 
n = 21
Hence, the value of n is 21 and this is a 21-sided polygon.