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
The answer to your question is yes
heather can do 2 problems in 10 minutes....60 minutes in an hr
2/10 = x / 60...2 problems to 10 min = x problems to 60 min
10x = 120
x = 120/10
x = 12....so she can do 12 problems in 1 hr
Joel can complete 3 problems in 15 minutes...
3/15 = x / 60
15x = 180
x = 180/15
x = 12....so he can do 12 problems in 1 hr
so 24 problems can be done in 1 hr
Heather started with 3 problems done and Joel started with 2 problems done....added = 5 problems already done
and it is asking between 30 and 50 hrs.....so there is no equal sign in ur problem
ur answer is : 30 < 24x + 5 < 50 <==
