2

# equilateral triangle problem beginner

Tue 8 Dec, 2020 05:00 pm
a equilateral triangle with the sides 5cm and the area 7,5cm^2

what is the lenght of unkown side?

b * h = 15 cm^2
b*h/b = h
h = 3 cm
pythagoras gives us z = 4
and short side 1 cm

x = 5^2 + 1^2 = 10
root 10 ~ 3,2

x = 3,2

Is there similar problems like this in the beginner SAT? Very good example right? How would you explain this problem?
• Topic Stats
• Top Replies
Type: Question • Score: 2 • Views: 929 • Replies: 6
No top replies

ekename

2
Tue 8 Dec, 2020 09:39 pm
@TooFriendly112,
If you were told that the triangle has at least two identical sides equal to 5 (isosceles) then
[(1/2)b]^2 + h^2 = 25
(1/2)bh = 15/2
Substitute h into the first equation
Solve the quadratic, and b = 5 or 45
Or simply observe that an equilateral triangle has three equal sides.
There is no unknown side and the base = 5

0 Replies

roger

0
Tue 8 Dec, 2020 10:05 pm
@TooFriendly112,
TooFriendly112 wrote:

a equilateral triangle with the sides 5cm and the area 7,5cm^2
What definition of 'equilateral' are you using?
izzythepush

1
Wed 9 Dec, 2020 09:07 am
@roger,
I think they’re confusing equilateral and isosceles.
maxdancona

2
Wed 9 Dec, 2020 10:29 am
@izzythepush,
Don't be obtuse
roger

0
Wed 9 Dec, 2020 12:34 pm
@maxdancona,
I think he's right.

Oh, a pun!
maxdancona

1
Wed 9 Dec, 2020 01:57 pm
@roger,
Yes, and there were 9 others. I am trying to find some play on words that will get Izzy to express his approval of me. But, sadly...

... No pun in ten did
0 Replies

### Related Topics

Amount of Time - Question by Randy Dandy
Statistics - Question by ekkline
Math of infinity - Discussion by dalehileman
Probability Question. - Discussion by babemomlover

1. Forums
2. » equilateral triangle problem beginner