That would be :
4x – 10 = x2 – 5x + 10 ( y = 4x - 10 is substitute for y)
PROOF: y + 5x = x²<span> + 10
</span> (4x - 10) + 5x = x² + 10
4x - 10 = x² -5x + 10
<span>
</span>0 = x2 – 9x + 20<span> (liked terms are grouped and simplified)
PROOF: </span> 4x - 10 = x² -5x + 10
4x = x² -5x + 10 + 10
0 = x² -5x -4x + 20
0 = x² - 9x + 20
Solving:
x² - 9x + 20 = 0
x² - 5x - 4x + 20 = 0
(x - 5) (x - 4) = 0
⇒ x = 4 (as question says) OR x = 5
Answer:
marked price = $69,000
Step-by-step explanation:
cost price = $60,000
profit
= 15%
= 15% × cost price
= 15/100 × $60,000
= $9000
marked price
= cost price + profit
= $60,000 + $9000
= $69,000
Only two triangles:
The 90* angle is stable, so you can change only the position of the 50* and 40* angles.
1 triangle: 40* is right to the 90*
2 triangle: 40* is left to the 90*
Hope this helped you!