Answer:
x = 19
Step-by-step explanation:
123°+3x = 180°
3x = 180°-123°
3x = 57
x = 57/3
x = 19
The reason why we use 123° + 3x = 180° because both are adjacent angles. Adjacent angles add up to 180°
Step-by-step explanation:
x = father's age now
y = son's age now
x = 2y + 10
x - 20 = 5(y - 20) = 5y - 100
using the first in the second equation :
2y + 10 - 20 = 5y - 100
-10 = 3y - 100
90 = 3y
y = 30
x = 2y + 10 = 2×30 + 10 = 60 + 10 = 70
the father is now 70 years old, the son now 30 years old.
For this case we can make use of the Pythagorean theorem.
We have then:
(root (117)) ^ 2 = x ^ 2 + 6 ^ 2
Clearing x we have:
x ^ 2 = (root (117)) ^ 2 - 6 ^ 2
Rewriting:
x = root (117-36)
x = root (81)
x = 9
Answer:
The value of x is given by:
x = 9 cm
Answer: option d.
Step-by-step explanation:
We have the function:
y = f(x) = x^2 - 1
The output is 99 when y = 99, and the input is x.
Then we need to solve:
y = 99 = x^2 - 1
for x.
99 = x^2 - 1
99 + 1 =x^2
100 = x^2
√100 = x
10 = x
The correct option is d, input equals 10.