Answer:
12 inches
Step-by-step explanation:
Raj tested his new flashlight by shinning it on his bedroom wall the beam of the light can be described by the equation (x^2-2x) + (y^2-4y) - 31=0. how many inches wide is the beam of light on the wall
Solution
Given:
(x^2-2x) + (y^2-4y) - 31=0
By completing the square
(x^2-2x) + (y^2-4y) - 31=0
(x^2-2x+1-1) + (y^2-4y+4-4)-31=0
(x-1)^2 -1 + (y-2)^2 - 4 - 31=0
(x-1)^2 + (y-2)^2 - 1 - 4 - 31=0
(x-1)^2 + (y-2)^2 - 36=0
(x-1)^2 + (y-2)^2=36
Writing the equation in the form: (x-h)^2+(y-k)^2=r^2
(x-1)^2+(y-2)^2=6^2
From the above, r=6
Where,
r=radius
how wide is the diameter ?
radius=6
Diameter= 2 × radius
=2×6
=12 inches
Clear out any fractions by Multiplying every term by the bottom parts.
Add or Subtract the same value from both sides.
Divide every term by the same nonzero value.
Combine Like Terms.
Factoring.
Expanding (the opposite of factoring) may also help.
answer will be 2÷18=9
and the answer is 9
please mark this answer as brainlist
Answer:
The answer is 1
Step-by-step explanation:
7 ∙ 15 can be written as 105
Distributive property
= 7(10 + 5)