Kevin is 3 years older than Daniel. Two years ago, Kevin was 4 times as old as Daniel.Let k be Kevin's age and let d be Daniel's age.Which system of equations represents this situation?Choose 1 answer:(A) {k=d+3k−2=4(d−2)(B) {k−2=(d−2)+3k=4d(C) {d−2=(k−2)+3d=4k(D) {d=k+3d−2=4(k−2)
Q. Kevin is 3 years older than Daniel. Two years ago, Kevin was 4 times as old as Daniel.Let k be Kevin's age and let d be Daniel's age.Which system of equations represents this situation?Choose 1 answer:(A) {k=d+3k−2=4(d−2)(B) {k−2=(d−2)+3k=4d(C) {d−2=(k−2)+3d=4k(D) {d=k+3d−2=4(k−2)
Translate first sentence: Let's translate the first sentence "Kevin is 3 years older than Daniel" into an equation.If k represents Kevin's age and d represents Daniel's age, then the equation is:k=d+3This equation states that Kevin's age is Daniel's age plus 3 years.
Translate second sentence: Now let's translate the second sentence "Two years ago, Kevin was 4 times as old as Daniel" into an equation.Two years ago, Kevin's age would be k−2 and Daniel's age would be d−2. According to the sentence, Kevin's age at that time was 4 times Daniel's age at that time. So the equation is:k−2=4(d−2)This equation states that two years ago, Kevin's age was 4 times what Daniel's age was at that time.
Combine equations into a system: Now we need to combine the two equations we have derived into a system of equations. The correct system of equations that represents the situation is:(A)
\begin{cases}
k = d + 3, \
k - 2 = 4(d - 2)
\end{cases}
This system correctly translates the given information into mathematical equations.
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