how to use the triangle method to solve for an unknown.. how to put formulas into the triangle. the...
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How to use the triangle method to solve for an unknown..
How to put formulas into the triangle.
The ‘signs’ of the triangle.
What is the unknown?
What are the other two units?
Solving math problems on the Science TAKS.
How to solve for an unknown using the “reverse the sign” method.
How to solve for an unknown using the “cross multiply” method.
Calculator clues.The formula chart
What is the unknown?Home
Look at the last sentence of the question. Double underline the unknown.
See sample
The unknown usually follows after “what” or “how many” or “when” or “how far” etc.
Anything moving vertical
Push current Resistance
Velocity and speed are the same thing, except velocity should include the direction that the object is going. Sometimes on TAKS they use the word ‘velocity’ equally as ‘speed’.
See how to put formulas into a ‘triangle’
Home
A mechanic used a hydraulic lift to raise a
12,054 N car 1.89 m above the floor of a
garage. It took 4.75 s to raise the car. What
was the power output of the lift?
A 489 W
B 1815 W
C 4796 W
D 30,294 W
What are the other two units?Home
Sometimes there are clearly only two other numbers in the question.The units of those numbers tell you about the formula to look for on the formula chart.
Sample of units and their meaning on the formula chart.
Other times, only one number is given and an illustration gives the other number.
1. Sample of only one number given.
2. Sample of when only one number is given & you use the gravity number.
Back
Unit On the formula chart
kg or g
L or mLoC
km or m or cm
hour or sec
N
Mass
Volume
Temperature
Distance
Time
Force
Which wave has the greatest velocity?
Velocity = frequency times wavelength
1 x 2
2 x 8
3 x 3
4 x 1
Back
An ant crawled from Point A to Point B in4.0 seconds. To the nearest tenth, what was the ant’s speed in centimeters per second? Record and bubble in your answer on the answer document.
4cm ÷ 4 s = 1 cm/s
Back
How many newtons of force does a 50.0 kg
deer exert on the ground because of gravity? Record and bubble in your answer on the answer document.
490
Force = mass x acceleration of gravity50 kg x 9.8 =
Home
How to use the triangle method
Home
÷ ÷
x
Cover the unknown with your finger. Do the function between the other two.
c
c = a ÷ b b = a ÷ ca= b x c
a
b
How to put formulas into the triangle.
Home
If part of the formula is already on top (numerator) it stays on the top.
If the formula doesn’t have a fraction, the ‘loner’ gets to be on top.
d
tsd
m
v
momentum
mass velocity
force
mass acceleration
work
force distance
Solving for an unknown using the “reverse the sign” method:
If distance is the unknown, x time
Speed x time = distance
x time
Speed = distance / time
Speed = distance / timeSpeed = distance / time
Another sample of “reverse the sign”
Solving for an unknown using the “reverse the sign” method:
Home
If time is the unknown,
Speed = distance / time
Speed = distance/time ÷ distance
Speed ÷ distance = time
Speed ÷ distance = distance/time ÷ distance
Solving for an unknown using the “cross multiply” method:
Home
If time is the unknown,
distance x 1 ÷ speed = time
Speed = distance 1 time