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.
Answer:
h = 
- r
Step-by-step explanation:
The question requires you to make h the subject of the formula.
S = 2πrh + 2πr²
subtract 2πr² on both sides.
S - 2πr² = 2πrh - 2πr² - 2πr²
S - 2πr² = 2πrh
Dividing both sides by 2πr
(S - 2πr²)/2πr = 2πrh/ 2πr
h = - r
2x-438 = -438+2x= 2(x-219)
Answer:
Divide by 2
q^2+4q=3/2
q^2+4q(4/2)^2=3/2+(4/2)^2
(q+4/2)^2=3/2+16/4
taking the square root of both side
√(q+4/2)^2=√(3/2+16/4)
Note that the square will cancel the square root then you will take LCM on the right hand side
q+4/2=√6+16/4
q+4/2=√22/4
q= -4/2+-√22/4
q=(-4+_√22/4)
