Answer:
20
Step-by-step explanation:
→ First find the value of x and y
x + y = 5
x - y = 4
→ Add the equations to cancel out the y's
2x = 9
→ Divide both sides by 2 to find the value of x
x = 4.5
→ Substitute x = 4.5 back into x - y = 4 to find the value of y
4.5 - y = 4
→ Minus 4.5 from both sides to isolate -y
-y = -0.5
→ Multiply everything by -1
y = 0.5
→ Substitute x = 4.5 and y = 0.5 into x² - y²
4.5² - 0.5² = 20.25 - 0.25 = 20
It’s true!! Hope this helped!!!!
Answer:
reflection
Step-by-step explanation:
its a reflection across the y axis
Answer:
f=11
Mode=4
Median=4
Explanation:
We are given that
a.Mean of the exam score,
=3.5
Score(x) frequency C.F
1 1 1
2 3 4
3 f 15(4+f=4+11)
4 13 28
5 4 32
Using the formula
b.Mode:The number which is repeat most times .
4 repeat most times
Hence, mode of all exam scores=4
N=32
N is even
Median=
<span>2n + 5 – (3n + 7) + 4n – 9
</span> <span>6n + 5 – (3n + 7) – 9
</span> <span>6n – 4 – (3n + 7)</span>
<span>6n – 4 – 3n – 7
</span> <span>3n – 4 – 7
</span> <span>3n –11</span>
