7+4a=55
4a=55-7
4a=48
a=48/4
a=12
We know that
[scale]=[doll house]/[<span>real house]
[scale]=12 in/3 ft
</span><span>The living room in stacy's house is 18 feet by 12 feet
</span>so
for 18 ft
[doll house]=[scale]*[real house]-----> (12/3)*18--------> 72 in
for 12 ft
[doll house]=[scale]*[real house]-----> (12/3)*12--------> 48 in
The living room in doll house is 72 in by 48 in
The living room area in doll house is (72*48)-----> 3456 in²
<span>Tom will need for the living room in Stacy's doll house 3456 in</span>² <span>of carpeting
the answer is </span>3456 in² of carpeting
Y=-4x²+4x-1 this quadratic equation is of the form ax² + bx + c
and its discriminante is ( Δ = b²- 4ac)
:
So Δ = b² 4ac ==> (4)² - 4(-4)(-1)==> (16) -16 = 0
When Δ = 0, the parabola intercept x=axis in one & only one point
And the x-intercept = -b/2a = (-4)/[2.(-4)] ==> x = 1/2
Let x = number of $10 coins.
The total number of coins is 44, therefore there are (44-x) $20 coins.
Total value:
10x + 20(44-x) = 620
-10x + 880 = 620
-10x = -260
x = 26 (number of $10 coins)
44-x = 44-26 = 18 (number of $20 cons)
Answer:
26 $10 coins
18 $20 coins
Step-by-step explanation:
8x² + 8x - 21 = 0
8(x² + x) - 21 = 0
8(x + 0.5)² - 23 = 0
8(x + 0.5)² = 23
(x + 0.5)² = 23/8.
