Difference between revisions of "1963 TMTA High School Algebra I Contest Problem 28"

Latest revision as of 14:43, 26 March 2023

If we add its square to a certain number, the sum is $72.$ Find the number.

$\text{(A)} \quad 9 \quad \text{(B)} \quad 6 \quad \text{(C)} \quad 36 \quad \text{(D)} \quad -9 \quad \text{(E) NOTA}$

Let the number be $x.$ Then we have $x^2 + x = 72.$ Solving yields $x = -9$ and $x=8.$

We see that $x=-9$ is an option, so the answer is $\boxed{\text{(D)}-9.}$

(The previous answer was $\text{(E) NOTA}$ , but that is not necessarily true because $x=-9$ is still a possible value for that "certain number".)

@@ Line 7: / Line 7: @@
 Let the number be <math>x.</math> Then we have <math>x^2 + x = 72.</math> Solving yields <math>x = -9</math> and <math>x=8.</math>
-We see that <math>x=-9</math> is an option, so the answer is <math>\boxed{\text{(D) -9}.}</math>
+We see that <math>x=-9</math> is an option, so the answer is <math>\boxed{\text{(D)}-9.}</math>
-(The previous answer was <math>\boxed{\text{(E) NOTA}}</math>, but that is not necessarily true because <math>x=-9</math> is still a possible value for that "certain number".)
+(The previous answer was <math>\text{(E) NOTA}</math>, but that is not necessarily true because <math>x=-9</math> is still a possible value for that "certain number".)
 == See Also ==

1963 TMTA High School Mathematics Contests (Problems)
Preceded by Problem 27	TMTA High School Mathematics Contest Past Problems/Solutions	Followed by Problem 29