Consider the contrapositive of the statement you want to prove.
The contrapositive of the logical statement
<em>p</em> ⇒ <em>q</em>
is
¬<em>q</em> ⇒ ¬<em>p</em>
In this case, the contrapositive claims that
"If there are no scalars <em>α</em> and <em>β</em> such that <em>c</em> = <em>α</em><em>a</em> + <em>β</em><em>b</em>, then <em>a₁b₂</em> - <em>a₂b₁</em> = 0."
The first equation is captured by a system of linear equations,

or in matrix form,

If this system has no solution, then the coefficient matrix on the right side must be singular and its determinant would be

and this is what we wanted to prove. QED
Answer: 70
Step-by-step explanation:
a^2 + b^2 = c^2
24^2 + b^2 = 74^2
576 + b^2 = 5,476
-576 -576
b^2 =4,900
(square root)
b =70
Answer:
The transformed points of the triangle ABC are
,
, 
Step-by-step explanation:
The new points after applying the scale factor are, respectively:






Answer:
<u><em>The Father is currently 47 and the Son is 7</em></u>
Step-by-step explanation:
Let F and S be the present ages of Father and Son, respectively.
We are told that <u>(F-2) = 9(S-2)</u> [2 years ago, father age was nine times the son age]
We also learn that <u>(F+3) = 5(S+3)</u> [3 years later it will be 5 times only]
Take the first expression and isolate one of the variables (S or F). I'll isolate F:
(F-2) = 9(S-2)
F = 9S - 16
Now use this in the second expression:
(F+3) = 5(S+3)
((9S-16)+3) = 5(S+3)
9S-13 = 5S+15
4S = 28
S = 7
Since F = 9S-16,
F = 9*(7)-16
F = 47
<u><em>Father is 47 and Son is 7</em></u>
CHECK:
Was the father 9 times the age of his son 2 years ago?
Father would have been 45 and son 5. Yes, 9*5 = 45
In 3 years will he be 5 times older than his son? Yes, Father would be 50 and son would be 10. 5*(10) = 50