Answer:
Sister = 15 years old
Brother = 12 years old
Step-by-step explanation:
Right now, if the brother is B years old and the sister is S years old, B = (4/5)S because the ratio from brother to sister is 4:5, so if one unit is X, B = 4X and S = 5X
Three years ago, the brother was B-3 years old and the sister was S-3 years old. Keeping one unit as X, we have
B = 3X
S = 4X
B-3 = (3/4)(S-3)
Therefore, we have a system of equations
B = (4/5)S
B-3 = (3/4)(S-3)
Substitute (4/5)S for B into the second equation to only have one variable
(4/5)S - 3 = (3/4)(S-3)
(4/5)S - 3 = (3/4)S - 9/4
add 3 to both sides and subtract (3/4)S from both sides to isolate the variable and its coefficient
(1/20)S = 3/4
multiply both sides by 20 to isolate the S
S = 15
B = (4/5)S = 12
I would think the answer is -16
but that's is what i think
Answer:
2×2=4
Step-by-step explanation:
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The function will exist on all real numbers. Hence the domain of the exponential function given is all real numbers
<h3>Domain of a function</h3>
The domain are independent values of an expression for which it exist. The standard exponential equation is expressed as y = ab^x
Given the exponential function as shown:
y = 5(3)^x
The function will exist on all real numbers. Hence the domain of the exponential function given is all real numbers
Learn more on domain here: brainly.com/question/26098895
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Answer:
it will 7.5×10^3 hope it helps
