Answer:
John’s age is 8 years
Step-by-step explanation:
Let
x -----> John’s father's age
y -----> John’s age
z -----> John’s sister's age
we know that
-----> equation A
-----> equation B


-----> equation C
Substitute equation A and equation B in equation C and solve for y

Multiply by 2 both sides to remove the fraction



<em>Find the value of x</em>
<em>Find the value of z</em>

therefore
John’s father's age is 40 years
John’s age is 8 years
John’s sister's age is 4 years
Answer:
a = 
b= 4
Step-by-step explanation:
It's a 30-60-90 triangle based on the given picture. A right triangle too
Use sine, cosine, and tangent to solve for the side.
To find b, you can use sin(30) = b/8 because sin(angle) = opposite/hypotenuse.
OR you can use the rule for 30-60-90 triangle, which is x for short leg, 2x for hypotenuse, and
for long leg
So either way, b = 4
To find a, you can use cos(30) = a/8 because cos(angle) = adjacent/hypotenuse.
OR you can use the same rule, 30-60-90 triangle to save time
a will end up = 
Zero-Exponent Rule: a0 = 1, this says that anything raised to the zero power is 1. ... Negative Exponent Rule: , this says that negative exponents in the numerator get moved to the denominator and become positive exponents. Negative exponents in the denominator get moved to the numerator and become positive exponents.
The total number of produced details increased by 6.4%
suppose the starting number was x.
suppose x=100
100 +12%= 112
112-5%=106.4
106.4-100=6.4
6.4%
The domain of the function y=tan(x) ) is all real numbers except the values where cos(x) is equal to 0 , that is, the values π/2+πn for all integers n . The range of the tangent function is all real numbers.