The little square means a right angle which is equal to 90 degrees.
X + 30 = 90
X = 60 degrees
Let t represent Todd's age now.
.. 4(t -3) -(t -3) = 81 . . . . . . 3 years ago, their differnce in ages was 81.
.. 3t -9 = 81
.. t = (81 +9)/3 = 30
Todd is 30 now.
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You can also work this by considering "ratio units." 3 years ago, the ratio of their ages was 4:1, a difference of 3. That difference corresponds to 81 years, so each "ratio unit" represents 81/3 = 27 years. Todd's age then was 1 ratio unit, 27 years. Now, Todd's age is 30.
The function can use all values of x which means x is in between -inf and +inf. The first option expresses this.
Answer:
Length = 40
Height = 20
Step-by-step explanation:
If you multiply 40 x 20, it equals 800
20 is also half of 40 as well.