Answer:
x + y = 4
Step-by-step explanation:
Given that, (x + iy)(1 - 3i) = 10, then we have to calculate x + y.
Now, (x + iy)(1 - 3i) = 10
⇒ x(1 - 3i) + iy(1 - 3i) = 10
⇒ x - 3xi + iy - 3yi² = 10
⇒ (x + 3y) + i(y - 3x) = 10
Now, comparing the real and imaginary part of both sides we get,
(x + 3y) = 10 ............. (1) and
y - 3x = 0
⇒ y = 3x ............... (2)
Solving equations (1) and (2) we get
x + 3(3x) = 10
⇒ x = 1
So, y = 3x = 3
Therefore, x + y = 1 + 3 = 4 (Answer)
Answer:
Surface area = 70π cm²
Step-by-step explanation:
Surface area = πr² + πrl
Surface area = (π × 5 × 5) + (π × 5 × 9)
Surface area = (25π) + (45π)
Surface area = 70π cm²
Eight hundredths
0.08
You already got it with the number part ;)

- subtract the 12 from both sides so that it becomes the last constant term in the quadratic equation which should now equal 0.
- take the 4x
- half the coefficient of 4 (2)
- square it (4)
- add it to the equation (+4)
- subtract it from the equation (-4)
- factorise the square (x+2)^2 expands to (x^2 + 4x + 2) as {a+b}^2={a^2 + ab + ba + b^2}
- now the equation is in turning point form.
- to find x, add 16 and square root 16 and (x+2)
- subtract 2 from positive or negative 4 (as -4^2 and 4^2 both equal 16).
- This should give you two values for x, -6 and 2.
I really hope that this helped :)
Answer: Option 4 i think. But i m still having confusions between option 4 and 2.