Answer:
14
Step-by-step explanation:
9 10 11 12 13 14
Using the dot product:
For any vector x, we have
||x|| = √(x • x)
This means that
||w|| = √(w • w)
… = √((u + z) • (u + z))
… = √((u • u) + (u • z) + (z • u) + (z • z))
… = √(||u||² + 2 (u • z) + ||z||²)
We have
u = ⟨2, 12⟩ ⇒ ||u|| = √(2² + 12²) = 2√37
z = ⟨-7, 5⟩ ⇒ ||z|| = √((-7)² + 5²) = √74
u • z = ⟨2, 12⟩ • ⟨-7, 5⟩ = -14 + 60 = 46
and so
||w|| = √((2√37)² + 2•46 + (√74)²)
… = √(4•37 + 2•46 + 74)
… = √314 ≈ 17.720
Alternatively, without mentioning the dot product,
w = u + z = ⟨2, 12⟩ + ⟨-7, 5⟩ = ⟨-5, 17⟩
and so
||w|| = √((-5)² + 17²) = √314 ≈ 17.720
31 degrees, 31 degrees, 118 degrees
Step-by-step explanation:
Step 1 :
Let x be the measure of 2 angles of the given isosceles triangle with same measure
Let y be the measure of 3rd angle
So we have x + x + y = 180
Step 2 :
Given that the measure of 3rd angle of triangle is 25° more than three times the measure of either of the other two angles
So we have , y = 3 x + 25
Step 3:
Substituting for y in the first equation we have,
x + x + 3 x + 25 = 180
=> 5 x + 25 = 180
=> 5 x = 180-25 = 155
=> x = 155/5 = 31
Hence the 2 angles of the triangle are 31 degrees.
Step 4:
we have y = 3 x + 25
=> y = 3 * 31 + 25 = 118
Hence the 3rd angle of given triangle is 118 degrees
