If 2x(x + y + z) = 250, 2y(x + y + z) = 100, 2z(x + y + z) = 100, then find the value of (3x + 6y + 15z).
95
Add the three given equations: $2x(x+y+z) + 2y(x+y+z) + 2z(x+y+z) = 250 + 100 + 100$, so $2(x+y+z)^2 = 450$, giving $(x+y+z)^2 = 225$ and $x+y+z = 15$.
Substitute $x+y+z = 15$ back: $2x \times 15 = 250 \Rightarrow x = 25/3$; $2y \times 15 = 100 \Rightarrow y = 10/3$; similarly $z = 10/3$.
Then $3x + 6y + 15z = 3(25/3) + 6(10/3) + 15(10/3) = 25 + 20 + 50 = 95$.
Hence, 95.
If x + 2y = 27 and x - 2y = -1, find the value of y.
Solve: If 8x + 5y = 9 and 3x + 2y = 4, find the value of x.
A.-2
B.5
C.2
D.-5
If tan 3 θ = cot(θ - 22°), where 3 θ is an angle, find the value of θ.
1 + tan 15° cot 75° is equal to:
The value of cot (-315°) is :
θ = 135°; γ = 15°.
What is the value of 2 cos(θ) sin(γ)?
If tan(90 – θ) = \(\frac{2}{\sqrt3}\), then the value of \(2\sqrt3\) tan θ + 1 is: