Answer:
x = ± 4
y = - 2
Step-by-step explanation:
y = 0.5x² - 10 ------------------------(I)
y = -x² + 14 ------------------------(II)
Substitute the y value in equation (II)
0.5x² - 10 = -x² + 14 {Add x² to both sides}
0.5x² + x² -10 = 14 {combine like terms}
1.5x² - 10 = 14 {Add 10 to both sides}
1.5x² = 14 + 10
1.5x² = 24 {Divide both sides by 1.5}
1.5x²/1.5 = 24/1.5
x² = 16
x = ±4
Substitute x = 4 in (I)
y = 0.5 * 4² - 10
= 0.5*16 - 10
= 8- 10
y = -2
Substitute x = -4 in (I)
y = 0.5 * (-4)² - 10
= 0.5*16 - 10
= 8- 10
y = -2
Answer:
Step-by-step explanation:
an exponential equation has the form y=ar^x where y=final amount, a=initial amount, r=rate, and x=time, in this case
y=200(1.18)^x
Set up a proportion
42.50/5=x/8
5x=340
x=68
He would earn $68
Answer:
<em><u>blue</u></em><em><u> </u></em><em><u>pens</u></em><em><u>=</u></em><em><u>288</u></em>
Step-by-step explanation:
<em>blue</em><em> </em><em>pens</em><em>=</em><em>720×40%</em>
<em>blue</em><em> </em><em>pens</em><em>=</em><em>720×40/100</em>
<em>blue pens</em><u>=</u><u>288</u>
