By solving the quadratic equation using completing the square method we got that Penelope should have added 4 to both sides instead of adding 1.
<h3>What is quadratic equation ?</h3>
Any equation of the form
where x is variable and a, b, and c are any real numbers where a ≠ 0 is called quadratic equation .
Given work of Penelope is

Now we can see that Penelope determined the solutions of the quadratic function by completing the square. so he must have been done as following

By solving the quadratic equation using completing the square method we got that Penelope should have added 4 to both sides instead of adding 1.
To learn more about quadratic equations visit : brainly.com/question/1214333
I don’t speak Spanish but if you put the English trans in the comments I’d love to answer
Answer-
The number is 5
Explanation-
let the number be x
according to the condition
2x-(x-7)= 12
2x-x+7=12
x+7=12
x+7-7=12-7
x=5
therefore the required number is 5
<h2><u>Complete Question: </u></h2>
Learning Task 1: Identify similar and dissimilar fractions. On your note- book write S if the fractions are similar and D if dissimilar.
1. 
2. 
3. 
4. 
5. 
<h2><em><u>The answers:</u></em></h2>
1.
- Similar (S)
2.
- Similar (S)
3.
- Dissimilar (D)
4.
- Dissimilar (D)
5.
- Dissimilar (D)
Note:
- Similar fractions have the same denominator. i.e. the bottom value of both fractions are the same.
- Dissimilar fractions have different value as denominator, i.e. the bottom value of both fractions are not the same.
Thus:
1.
- They have equal denominator. <u><em>Both fractions are similar (S).</em></u>
2.
- They have equal denominator. <em><u>Both fractions are similar (S).</u></em>
3.
- They have equal denominator. <em><u>Both fractions are dissimilar (D).</u></em>
4.
- They have equal denominator. <u><em>Both fractions are dissimilar (D).</em></u>
5.
- They have equal denominator. <em><u>Both fractions are dissimilar (D).</u></em>
Therefore, the fractions in <em><u>1 and 2 are similar (S)</u></em> while those in <em><u>3, 4, and 5 are dissimilar (D).</u></em>
<em><u></u></em>
Learn more here:
brainly.com/question/22099172