Math Homework Help

[Jessica]

Given that ΔABC is congruent to ΔDEF. the measure of angle A is 70°, the measure of angle B is 60°, the measure of angle C is 50°, the measure of angle D is 3x + 10°, the measure of angle E is y/3 + 20° and the measure of angle F is z² + 14°.
Since the triangles are congruent, the angles and sides measures are the same. They are congruent. We are looking for the angles so we have to set each angle = to each other.

Find the values of x, y, and z.



I know it now.
angle A is congruent to angle D, so 3x + 10 = 70. x = 20
angle B is congruent to angle E, so y/3 + 20 = 60. y = 120
angle C is congruent angle F, so z² + 14 = 50. z = 6

[CrOtALiTo]

I don't like the maths.

[sosia]

Jchen, you should first say what do you think/have done, like in the grammar homework
Definition: here
Congruent triangles have the same angle and side, so they have the same angle --> so a=d, b=e, c=f
-->
70= 3x +10 --> x= 60/3 = 20
60=y/3 + 20--> y= 3*40 = 120
50=z^2 + 14 --> z= sqrt(36) = 6
Comprobation (not needed, but its good for testing):
all angles of a triangle must add 180 º
(3x +10) +(y/3 + 20)+(z^2 + 14)=180
(3*20+10) + (120/3 + 20) + (6^2 + 14) = 180
70 + 60 + 50 = 180

Be carefull! you can use this because it's already sayed they are congruent.
Two triangles with the same angles are similar, not necesarilly congruent.
The "congruent" triangles will have the same shape and size, but one may be a mirror image of the other.
The "similar" triangles will have the same shape, but not necessarily the same size.
To see if they are "congruent"-->Imagine the triangles are cardboard
One way to think about triangle congruence is to imagine they are made of cardboard. They are congruent if you can slide them around, rotate them, and flip them over in various ways so they make a pile where they exactly fit over each other.

Saludos

[Rusty]

Originally Posted by CrOtALiTo

I don't like the maths.

Correction:
No me gustan las matemáticas.
= I don't like math.
= I don't like arithmetic.

Otras asignaturas:
No me gusta la lectura.
= I don't like reading.

No me gusta la escritura.
= I don't like writing.

En inglés, estas tres asignaturas se denomina como "the three Rs" porque cada palabra empieza con el mismo sonido (R) - reading, writing, 'rithmetic.

[Jessica]

Originally Posted by sosia

Jchen, you should first say what do you think/have done, like in the grammar homework
Definition: here
Congruent triangles have the same angle and side, so they have the same angle --> so a=d, b=e, c=f
-->
70= 3x +10 --> x= 60/3 = 20
60=y/3 + 20--> y= 3*40 = 120
50=z^2 + 14 --> z= sqrt(36) = 6
Comprobation (not needed, but its good for testing):
all angles of a triangle must add 180 º
(3x +10) +(y/3 + 20)+(z^2 + 14)=180
(3*20+10) + (120/3 + 20) + (6^2 + 14) = 180
70 + 60 + 50 = 180

Be carefull! you can use this because it's already sayed they are congruent.
Two triangles with the same angles are similar, not necesarilly congruent.
The "congruent" triangles will have the same shape and size, but one may be a mirror image of the other.
The "similar" triangles will have the same shape, but not necessarily the same size.
To see if they are "congruent"-->Imagine the triangles are cardboard
One way to think about triangle congruence is to imagine they are made of cardboard. They are congruent if you can slide them around, rotate them, and flip them over in various ways so they make a pile where they exactly fit over each other.

Saludos

I already know about congruent triangles. I just need some ideas on how to start. Then I'll be fine

[CrOtALiTo]

Thanks Rusty for your corrections.

[Rusty]

You're welcome.

[Jessica]

I found the values of x, y, and z already.

[Tomisimo]

Originally Posted by CrOtALiTo

I don't like the maths.

In British English, maths is the correct abbreviation for mathematics. In American English math is the correct abbreviation.

[Jessica]

interesting.....very interesting ^_~