X = <span>weight of the baby.
y = </span>weight of the doctor.
z = weight of the nurse.
x + y = 78 so y = 78 - x
x + z = 69 so z = 69 - x
x + y + z = 142
substitute y = 78 - x and z = 69 - x into x + y + z = 142
x + y + z = 142
x +78 - x + 69 - x = 142
-x + 147 = 142
-x = - 5
x = 5
answer
<span>the weight of the baby was 5 kg</span>
The answer is <span>$103.
To determine </span><span> how much Eileen will spend on gasoline, first we need to calculate how many gallons she needs.
If she drives 850 miles and </span><span>her car gets 23 miles per gallon, we can use the proportion:
850 miles : x gallons = 23 miles : 1 gallon
Crossing the products:
x = 850 miles </span>× 1 gallon ÷ 23 miles
x = 36.96 gallons
Thus, Eileen needs 36.96 gallons of gas. If the cost per gallon of gas is$2.79, using the proportion:
36.96 gallons : x = 1 gallon : <span>$2.79
x = 36.96 gallons </span>× $2.79 <span>÷ 1 gallon
x = </span>$103.12
x ≈ $<span>103</span>
Answer:
$28.
Step-by-step explanation:
p(x) = -2(x - 9)^2 + 100
If the prices (x) = 15 dollars we work out the profit by substituting x = 15 in the above formula:
p(15) = -2(15 - 9)^2 + 100
= -2 * 6^2 + 100
= $28.
Answer:
a) 
b) 
c) 
Step-by-step explanation:
Given the curve

a) If the x-coordinate of P is
, then the y-coordinate is
so point P has coordinates 
If the x-coordinate of Q is
, then the y-coordinate is
so point Q has coordinates 
b) The gradient of the secant RQ is

c) If
then the gradient 
Answer:
A
Step-by-step explanation:
Being similar means that the shapes will have the same shape and dilation factor between sides, but if they are not congruent then the size will not be the same.