Answer:
x = 7
Step-by-step explanation:
Because this is a right triangle, one angle is a right angle (90°). All triangles have all three angle measures adding up to 180°, so the other two angles' measures add up to 90° (90 + 90 = 180).
Combine like terms of the angle measures.
6x + 9x = 15x
-3 + (-12) = -15
15x - 15
Because the sum of the measures of the two angles have to equal 90,
15x - 15 = 90
Add 15 from both sides.
15x = 105
Divide both sides by 15.
x = 7
To check, substitute 7 in both expressions.
6(7) - 3 = 39
9(7) - 12 = 51
39 + 51 + 90 (the measure of the right angle) = 180, so the value of x is 7.
I hope this helped :)
Jenny won the race as she finished the race much more quickly and has greater average speed than Lester.

Jenny: distance/time = 100/15.2 = 6.58 m/s = 6.6 m/s
Lester: distance/time = 100/15.7 = 6.37 m/s = 6.4 m/s
Answer:


Step-by-step explanation:
Note that the entire segment RT is the combined lengths of RS and ST. So:

We know that RT is 108, RS is (9y+5), and ST is (3y+7). Substitute:

On the right, combine like terms:

Add:

Subtract 12 from both sides. The right cancels:

Divide both sides by 12:

So, the value of y is 8.
To find RS and ST, substitute 8 for y. So:

Substitute 8 for y:

Multiply:

Add:

Do the same for ST:

Substitute 8 for y:

Multiply:

Add:

15x^2+21x+6 that’s the answer
Answer:
z = 8
Step-by-step explanation:
3/4 (z+4)=9
3/4z + 3 = 9
3/4z = 6
z = 8